Handedness in Youth Baseball

A big deal is made in Major League Baseball (MLB) about which hand a player uses to throw and to hit. The differences between handedness breakdowns of MLB players and in the population at large are quite dramatic.

But what about youth baseball? How does an understanding of MLB handedness issues impact opportunities for young baseball players? How do coaches assign positions to left-handed versus right-handed players?

The answers depend heavily on coach philosophies, which vary. Given that my son is left-handed, I’ve seen firsthand how the positions he has been allowed to play in youth baseball have varied depending on context and coach philosophy.

In this article, I first share the data on MLB handedness and the reasons why handedness is so important for professional baseball players. The remaining part of the article explores handedness in youth baseball.

MLB Handedness Stats and Analysis (from Lahman Baseball Database)

Before discussing handedness in youth baseball, I think it’s worth exploring the reality of handedness in the major leagues. Putting on my data science hat for this article—I obtained the Lahman baseball data set from baseball inception through the end of the 2018 season and wrote some simple R code to extract, reshape and display the data in order to answer a few handedness questions.

It’s worth noting that the Lahman database is the highest quality data set for baseball available at no cost. What started as a one man effort in 1994 has grown tremendously, and now a team of researchers have collected their efforts to make this the largest and most accurate online source for baseball statistics available anywhere.

The Lahman handedness data is missing for many players before 1930, so I looked at a subset of the data from 1930 through today. Here’s what handedness looks like in modern times, for all MLB players (both pitchers and non-pitchers) who played at least 1 game between 2010 and 2018:

MLB Player Handedness 2010-2018

Bats	Throws	# Players	Percentage
Right	Right	2021	61.20%
Right	Left	101	3.10%
Left	Left	581	17.6%
Left	Right	370	11.2%
Left	Both	1	0.03%
Both	Right	213	6.4%
Both	Left	17	0.5%

Have these splits have changed over time? Not much.

First let’s look at hitting handedness over time:

Hitting Handedness since 1930

 

Pure right-handed hitting has gone down slightly over the past 90 years, with switch hitting increasing a bit in the 1970s to 1990s, and then left-only hitting increasing more since the turn of the century. The changes have been small enough that looking at the hitting handedness splits from recent times are hardly any different than looking at the whole data set.

Looking next at throwing handedness over time:

Throwing Handedness since 1930

 

Left-handed throwing increased slightly during this 89-year period, but it seems to have peaked in the last 2 decades of the 20th century and has since been in a slight declining trend. Again, the changes have been small enough that looking at the throwing handedness splits from recent times are hardly any different than looking at the whole data set.

It’s worth noting that left-handed U.S. males are roughly 12% of the overall population, yet:

• 26.7% of recent MLB pitchers threw left-handed
• 13.1% of recent MLB non-pitchers threw left-handed

So yes, there’s more demand for left-handed pitchers in professional baseball then there are left-handed male throwers in the overall population.

Notice though that only 13.1% of non-pitchers throw with their left hand. If left-handed hitters are so good, why aren’t there more left-handed position players?

This is partly answered in the next section which explains that, although left-handed hitting is valuable, right-handed throwing is important for fielding. Therefore, there are many non-pitchers who throw right but bat left or switch hit:

• 12.3% of recent MLB non-pitchers throw right but switch hit
• 19.4% of recent MLB non-pitchers throw right but hit left

I don’t know how rare throw-right-bat-left people are in the general population, but I would guess something like 1 in 500 or 1 in 1000. But given that right-handed throwers who can hit well left-handed account for 31.7% of MLB position players, it is very clear that this combination of handedness is very highly valued at the professional level. Being able to throw well right-handed and hit well left-handed is nearly as helpful as it is to be over 7′ tall for a professional basketball player.

The above stats clearly show that, at the professional level, baseball’s various handedness advantages result in different proportions of handedness for both throwing and hitting as compared with the population at large.

Why Handedness Matters so much in the Major Leagues

This section could be an entire article in and of itself, but I’m going to keep it brief and just summarize the primary reasons MLB handedness matters so much:

• The bodies of right-handed throwers are naturally positioned well for the throw to first base after fielding the ball at second base, shortstop, or third base. Left-handed throwers have to turn before making the throw, giving runners a few tenths of a second extra to get to first. Only right-handed throwers occupy these three positions in the MLB.
• Left-handed throwers have advantages playing as first basemen, but these advantages are so slight that both left-handed and right-handed throwers play first base. Big left-handed players who hit well but aren’t very mobile often play this position because they would hurt the team fielding elsewhere.
• Matchups between the pitcher and the hitter typically favor the hitter when handedness is opposite. Managers therefore switch pitchers frequently in close games to gain slight statistical advantages. However . . .
• Hitting left-handed is generally a big advantage, primarily because most pitchers are right-handed.
• Lefty batters also have the advantage of more frequently beating out soft grounders due to better initial body position when running to first base.
• In general, batters will have more difficulty with a left-handed pitcher whose velocity and “stuff” is identical to a right-handed pitcher because they don’t see left-handed pitching as often.

Despite position limitations, the smaller supply of talented left-handed pitchers and hitters causes them to be more sought after at college and professional levels of baseball. As detailed above in the “MLB handedness stats and analysis” section, the numbers are even more extreme for players who throw right but bat left.

College and High School

I have no statistical database to access for college and high school but I am under the impression from numerous conversations and articles read that the same advantages that work at the MLB level also work at the college and high school level.

The distribution of players with certain types of handedness is likely less extreme than in the MLB due to how rarely these traits appear in the population at large. But coaches generally place players in positions using the strategies used in the MLB, because they are trying their best to win games. Therefore, all else being equal, left-handed players will have an easier time getting on to a college team than right-handed players. This is especially true of players who bat left and throw right.

Youth Level: Overview

For players below the age of 13, baseball games are usually played on fields of reduced size. Some rules differ from MLB rules to reflect the smaller field size and lower skill levels. More importantly, game purpose ranges from “just for fun” recreation leagues to highly competitive teams that travel to other states to play against similarly competitive teams.

Below high school age, many players struggle with fielding, especially at ages under 11. Sometimes, a left-handed shortstop is better at fielding a grounder than any other player on the team. A short, right-handed fielder may be much better at catching bad throws to first base than big left-handed players. Should a coach therefore play these players at these positions, even though not traditional for their body types?

Opinions vary on how to assign fielding positions, depending on how much a coach emphasizes winning over development. Coaches also differ as to what they mean by “best for development.”

For example, some coaches believe that prior to age 13 (when play on the big field begins), players will better learn the sport of baseball if rotated through a wide variety of positions. Coaches following this philosophy rotate most players among all positions, regardless of handedness.

Other coaches believe that positions should be assigned as if the players were adults. For example, left-handed players will not play shortstop at the high school level or above, so better to prepare for the positions available in the long run, which are pitcher, first base, and outfield.

Life is simpler for the right-handed thrower, as all positions are possible at any age. However, even right-handed throwers can be subjected to specialization based on body type. Shortstop is typically occupied by the quickest, most athletic players, while big, slow players may end up with nowhere to play but first base or pitcher.

Of course, coaches often choose to play players at certain positions based on how ready they are, regardless of handedness. And coaches who prioritize winning over all else will place players in positions that will give the team the best chance of winning.

Youth Level: Throwing Handedness

For young baseball players who throw right-handed, life is simple. If you’re athletic and you work at your game, you can play any position. Shortstop is the most athletically demanding, while pitcher and catcher are the most impactful positions, so the players with greatest ability on a particular team usually play many innings at one or more of these three positions, even on teams where the coach rotates most players through most positions.

I have heard several coaches say that they would prefer if every right-handed thrower on their team was capable of playing shortstop well. Why? A player who can play shortstop can be easily trained to play any other position. This is an exaggeration, as the catcher position is difficult to master, but it’s a reasonable statement for the other positions.

Life is less simple for left-handed throwers. At the youngest ages, many coaches will play them at a wide variety of positions. However, as discussed earlier, some coaches treat pre-teen kids the same way they would treat players at the level of high school or beyond. The older kids get, the more this is done, until by age 11 it is rare to see a left-handed player playing third base, shortstop, second base, or catcher. In my experience, head coaches are a bit looser about the catcher position prior to high school.

There’s also the size issue. At high school level and above, coaches like big players at first base, and fast players in the outfield. The closer a player is to high school age, the more I see big left-handed players at first base, and smaller more agile left-handed players playing right field. So what this boils down to is:

• Big left-handed throwers who hit well play first base
• Smaller, more agile left-handed throwers who can hit for contact play outfield
• All left-handed throwers will be pitching some if their pitching skill is not too far behind the right-handed pitchers on the team

Left-handed players who don’t fit any of these profiles will be able to play in a recreation league, but will have a hard time making an all-star or travel team roster. Most of the left-handed throwers I’ve known over the years dropped out of baseball between the ages of 10 and 13. I sometimes wonder if part of the reason for that is that they are pigeon-holed into so few positions that they find the game less interesting than right-handed throwers.

There is another drawback for left-handed players that is a natural consequence of ordinary coach decisions on player rotation. It has to do with the skill distribution of right-handed players. Most teams will fill all but the outfield and first base positions with the highest performing right-handed throwers. The coach will rotate the remaining, less skilled right-handed players through outfield positions in order to make sure they get some playing time. Therefore, it happens that left-handed throwers who are quite good at their outfield position will often get subbed out for right-handed throwers who can’t play the position as well.

This happened frequently to my left-handed son at right field starting at the age of 9. Despite playing right field very well, including occasionally throwing out runners at 3rd and home, coaches would often put in a right-handed player with a weaker arm in order to make sure that the right-handed player got any playing time at all. If my son wasn’t pitching when this right-handed right fielder came in, he’d occupy the bench.

Here’s a bit more detail on how being left-handed played out for my small son over his years in youth baseball:

He had a few recreation league coaches who believed players would better learn the game if they played every position. My son therefore played all 9 positions despite being left-handed. After age 10, he played very little third base, shortstop, or second base, but still played catcher occasionally, even at the age of 14.

It’s clear that my son’s high school baseball future is left-handed pitching. But I believe that he better understands the game as a result of playing every position. Though he won’t play the catcher position in high school, he’ll be better able to work with catchers in his role as pitcher, thanks to innings played as catcher prior to high school.

Certain summer coaches have played my son only in right field when he wasn’t pitching. Small left-handed players like him are assigned to pitch or play outfield (usually right field) when the coach has the philosophy of training players on positions that will be available to them in high school. This also was beneficial, as he has learned the right field position thoroughly over the years.

With the benefit of hindsight, I think he was fortunate to get exposure to both development philosophies. However, when I saw him getting slotted into traditional lefty positions at the age of 8 through 10 on a couple of competitive summer teams, I was not happy about it as I thought specialization at age 8 was unnecessary and would hinder his development. By the ages of 12-14, I expected and embraced specialization as high school age approached.

By high school, the remaining left-handers are mostly either decent pitchers or big guys who can hit. Competent left-handed pitchers are valuable to a high school team, and even more valuable at the higher levels, partly due to their scarcity. After many years of being handicapped by left-handed throwing, a left-handed thrower sometimes becomes advantaged in high school and beyond.

An example of the left-handed advantage is how it is easier for a left-handed pitcher to earn a spot on a college baseball roster than a right-handed pitcher. Right-handed pitchers must throw with a very high velocity, typically high 80s, and at some Division I schools the average right-handed velocity is close to 90MPH. Left-handed pitchers, being in shorter supply, can usually make a roster with 2-3 MPH less velocity than right-handed pitchers.

Youth Level: Left-handed Hitting

Most people intuitively believe that a kid who throws right-handed should bat right-handed, and a kid who throws left-handed should bat left-handed. It turns out that science does not support this view.

Research strongly suggests that eye dominance is different from hand dominance. There is also some speculation that eye dominance matters more for hitting than hand dominance, though research on this point is not yet conclusive. Approximately 66% of the population is right-eye dominant, while 88% of the population is right-hand dominant.

Given the many advantages of batting left-handed, and the known fact that eye dominance is often not the same as handedness dominance, there is every reason to let kids experiment. At the ages of 5 and 6, kids can’t hit well from either direction. So why not let them try both?

A lot of parents and youth coaches insist on aligning hitting handedness with throwing handedness, likely because they’re not aware of the eye dominance research.

One of the funniest things I ever saw was a well-meaning parent who kept telling his right-handed player over many years that he needed to show he could hit well right-handed before it made any sense to experiment with switch hitting. When he was 11, this player was at a recreation league evaluation where many coach sons were trying to purposely tank their own scores to provide advantage to their team during the draft (yes, I know this is bad, but . . . so long as there is drafting in youth baseball, people will look for ways to manipulate that draft). Several other right-handed hitters batted left-handed and hit poorly. So, being a coach son, he also batted left-handed. He hit solid line drives and very hard grounders left-handed despite never getting practice hitting from that direction. It was better than his right-handed hitting that he’d practiced for years!

The point here is that there is no reason to stop kids from experimenting with batting left even if they are right-handed. Some coaches won’t let them hit left-handed, and they may get discouraged if they don’t have immediate success. But as mentioned earlier in this article, players who throw right and bat left are in short supply and high demand at the highest levels of baseball. So for a player with significant talent, let them experiment batting left-handed. Encourage it!

Is there Anything to Conclude?

For players who want to have fun playing baseball for a couple years with their local recreation league, does any of this matter? Probably not. The goal is to have fun, and experimenting with throwing or hitting with the opposite arm from what seems natural may detract from that fun. This describes over 80% of the players on any given recreation league team.

However, some players know at an early age that they love baseball and want to keep playing for as long as their talent and hard work lets them play. While learning to throw with the opposite arm is usually difficult, learning to hit from the other side is not as difficult, particularly for those whose eye dominance is opposite to their hand dominance.

For right-handed throwers who choose to experiment with batting left, it may hurt short run performance, but if they can actually learn to bat well left-handed, the long-term payoff could be significant.

For those players who already hit and throw left-handed, it’s worth understanding how coaches assign positions in both the short and long run. Lefties may have fewer playing position opportunities than right-handed players with comparable ability prior to high school. But for lefties who can pitch and who persevere, there will almost certainly be a spot on the roster for them to pitch on their high school team.

And for those of you who are youth baseball coaches—consider letting players experiment with left-handed hitting even if it hurts the team in the short run. You may be doing the kid a big favor in the long run.