xwOBA Part 2: The Oakland A’s and Balls in the Air

Oakland’s bats have come back to life and it is about time. Since the East Coast swing began on Friday the A’s have scored 33 runs in six games, good for 4th in baseball. Their 13 home runs are the most and their .345 wOBA is good for 11th. However, in the two weeks prior to this hot streak the team had mustered just 34 runs, three more than lowest scoring St. Louis Cardinals, and 11 home runs. By wOBA, however, the A’s ranked dead last.

Prior to a 14-day period when the A’s couldn’t hit their way out of a wet paper bag they were among the best offensive forces in the league. It’s amazing how quickly things can change, twice.

While the results suggest the A’s are a streaky offensive threat, the underlying numbers tell a different story. As I stated in my primer on xwOBA and what it means for batted balls a hard-hit ball that just happens to find a glove is not a failed at-bat. The A’s are unfortunately among the unluckiest teams when it comes to hard-hit balls becoming hits.

Oakland’s .347 xwOBA ties them with Washington for sixth-highest in MLB and shows that A’s hitters have what it takes to be one of the most potent offenses in baseball, even if the results aren’t always there. However, the results are often there as the A’s have the ninth-highest actual wOBA in the league. Still, the difference between Oakland’s xwOBA and actual wOBA is the 10th highest in baseball. The A’s are one of just four teams that ranks among the top-10 in all three wOBA, xwOBA, and xwOBA-wOBA (Cleveland, Boston, and Seattle are the other three).

Nine Oakland hitters with at least 30 PAs have a higher xwOBA than actual wOBA. Nearly the entire offense is underperforming their batted-ball numbers.

But who is under-performing the most?

Look past Jake Smolinski as he is no longer on the MLB roster and because none of his numbers are at all impressive. Next we have Matt Olson, which might be obvious. Among hitters with 70 or more batted-ball events Olson’s 93.4 average exit velocity is 10th in baseball, his 53 batted-balls at 95+ MPH ties him for 25th, and his 55.2% hard-hit rate is 4th best. Olson’s problem is that he just isn’t putting the ball in play enough. He is striking out 30% of the time with a zone-contact rate of 66.5%, which is down from 75.7% last year.

Like the rest of the A’s, Olson has come to life a bit, swatting home runs in 2 of his past 3 games. He’s also pushed his slugging percentage and wRC+ back over .400 and 100, respectively. His home run last night off Craig Kimbrel, while not a barreled ball, was an impressive home run nonetheless.

BaseballSavant.com

1. The ball was hit to the opposite field.
2. The ball cleared the green monster easily.

Olson is so powerful that all he needs to do is simply sneeze on the ball and it will travel. His average distance on batted balls is 209 feet, which is good for 11th best in the league.

Olson’s problem is that he just isn’t putting the ball in play enough. He is striking out 30% of the time with a zone-contact rate of 66.5%, which is down from 75.7% last year. If can fix his contact problem he should be due for an offensive explosion.

The next name on that list is what may surprise many of you. Stephen Piscotty has underwhelmed since he arrived in Oakland. I can’t say whether or not what was going on with his mother was affecting him at the plate, although I know I’d be affected, if the situation was reversed.

The truth is, however, that Piscotty has underperformed his batted-ball numbers since the start of last season. He was outstanding in 2016, but despite career-best plate discipline in 2017 his overall performance dropped because his power disappeared. His power has continued to lag in 2018, and is nearly identical to his 2017 output. What’s different? He has traded some flyballs for groundballs. He is still hitting his flyballs and line drives as hard and at a similar angle as in 2016 so the decrease in balls in the air could be making a difference.

The A’s are hitting a lot of home runs. The 8th most in the league, in fact. They also have hit more flyballs and line drives than two-thirds of the league. It’s no surprise that balls hit in the air have been crucial for this team’s run production, and will continue to be so. However, it is on balls hit in the air that A’s are under-performing their batted-balls the most.

The A’s are hitting the ball hard and in the air with frequency - both good things. However the failure to always capitalize on these batted-balls is what is causing the streakiness of this offense. However, as the weather is yielding more favorable hitting conditions and players regain their timing I’m confident the A’s will continue to see improvement on their batted-balls.