Ryan O’Hearn and the case against batting average

I’m going to be 100% honest with you, I was really worried about Ryan O’Hearn during his time at AAA this season. Last year with AAA Omaha, O’Hearn posted an OPS of .776 with 18 HR in 114 games, good for a 99 wRC+. Not great, but not bad for 23-year old in his first bout at the highest level of Minor League Baseball. With the signing of Lucas Duda this spring, it was apparent that O’Hearn would begin 2018 back with Omaha, and I was excited to see how he’d progress.

He somehow got worse, statistically speaking. His walk rate was up, his strikeout rate was down, he just wasn’t having the same success hitting the ball that he’d had in 2017. Part of that is thanks to a batting average on balls in play (BABIP) that had sunk down to .286. Part of that is surely due to an awareness from other teams of the damage that O’Hearn is capable of. Minor league exit velocity numbers are not always publicly available, but reports on O’Hearn suggested that he was hitting the ball as hard as ever.

Let me tell you that my worries have been put to ease a bit since Ryan O’Hearn made his big league debut on July 31st. O’Hearn debuted in style, hitting his first big league home run in his first big league game. Since then, O’Hearn has posted the second best OPS on the team, while also posting the worst batting average, by a long shot.

Batting average can be an incredibly fickle statistic. Take Monday night for example. O’Hearn hit a ball in his first at-bat that had an exit velocity of 8,000 mph (it was 105 but it sounded like 8,000) that the CF caught without moving too far to his left. Hardly a fair way to judge the at-bat, but it was penalty on his batting average nonetheless.

According to the data base over at Baseball Savant, Ryan O’Hearn currently has the 12th best average exit velocity among all MLB players who have hit at least 25 baseballs this season. His average exit velocity is 93.3 mph, and his xwOBA (expected weighted on base average) is a team leading .367. O’Hearn is destroying baseballs in a small sample size during his time in Kansas City, but his .125 BABIP may lead you to believe otherwise.

Enter “luck”.

Look...I am not ever going to tell you that BABIP = luck. It doesn’t. There are several ways for a player to consistently run up a high BABIP without being lucky. BABIP DOES NOT EQUAL LUCK.

However, in cases like the ball Ryan O’Hearn destroyed in his first at-bat last night, luck can sometimes explain some things. If O’Hearn hits that ball in the gap, it’s a sure-fire double. He didn’t, and he was out. SOMETIMES, a player makes an amazing play on a ball that drops for a hit 99% of the time. That’s just unlucky. Luck can help explain some BABIP mysteries, but it doesn’t explain 100% of cases.

My point in all of that is this: just because Ryan O’Hearn is currently hitting .182 doesn’t mean that should be your normal expectation for him. He is crushing baseballs at the moment, and guys who hit the ball that hard on a consistent basis usually find more success than O’Hearn has found in his brief time with the big league club.

Enter OPS.

OPS is how in-the-know baseball fans begin to weed through the luck. Ryan O’Hearn is walking in 11.1% of his plate appearances and is slugging .523. That will play in the major leagues. When his hits do fall, they are often times for extra bases. He’s not hitting his way on base very often, but if hits do start falling more frequently, his on-base percentage (OBP) should see a nice uptick due to his impressive walk rate.

Here’s a graph representing exit velocity’s relationship with batting average in the MLB this season, minimum 500 pitches seen:

As you can see, generally the harder you hit the ball, the better your batting average will be. There are some obvious outliers and extremes, but that’s a decent correlation. As hard as Ryan O’Hearn is hitting the ball this season, you could resonably expect him to have more success than he has in a small sample size.

That’s the problem with blind faith in batting average. You can’t account for luck, good defense, or a hitter’s ability to be on base using only batting average. When you look at the box score, you may find yourself concerned with Ryan O’Hearn’s batting average. Don’t be. He’s walking plenty and hitting for enough power to have success at this level. With the way he’s hitting the baseball, I’d expect him to start finding more holes and collecting more base hits as his sample size grows with plate appearances. I don’t expect him to be an All-Star, by any means, but Ryan O’Hearn has looked really good so far in the big leagues.