April 1-July 31:
Player A: 871 OPS, 132 wRC+
Player B: .881 OPS, 129 wRC+
August:
Player A: .599 OPS, 55 wRC+
Player B: 1.086 OPS, 185 wRC+
Any guesses? They both play for the Red Sox. They both are 23. One has had his name come up in MVP talks recently, and the other, not so much. Player A is, you guessed it, Xander Bogaerts. Player B is, you probably guessed this one too, Mookie Betts. It’s crazy to see how similar their respective seasons were going during the first four months, and how much their stocks have changed over the past month.
Mando already wrote about Betts’ MVP chances here, so I will take the other, less glamorous, half of the story.
When you look for an explanation for Bogaerts’ suddenly awful month, you’ll quickly notice that mostly everything has gone wrong. His exit velocity is down, his BABIP is down, he’s striking out more, he’s walking less, and so on. This doesn’t really tell us much other than he just hasn’t been that good.
So let’s take a step back and look at Xander from a fan’s perspective. What is he at his best? A line-drive, hard ground ball hitter who uses his natural inside-out swing to hit the ball to the opposite field. “Good” Xander actually reminds me of myself before my unavoidable retirement from baseball. I was a hitter when, at my best, was hitting line drives between the left and center fielders (I’m a lefty) on pitches that were middle and middle-away. If I was pitching against myself, I would throw exclusively inside fastballs and probably would ground out to second base nine times out of ten. For whatever reason, I could never quite figure out how to lift fastballs on the inner-half of the plate.
Bogaerts, a professional baseball player who’s still hitting .306/.361/.452, probably has figured out how to hit inside fastballs well, but maybe what was my downfall still affects him to a lesser extent.
Below you’ll see Bogaerts’ heat map on fastballs (the strike zone split up into quadrants) from April to July. The top number in each box represents the number of fastballs that were thrown in that location over that time period and the bottom number is the same in percentage form. The red boxes show that more pitches were thrown there and blue boxes show where fewer pitches were thrown.
Location of Fastballs Seen, April to July
You can see that, over the first four months of the season, pitchers were throwing Bogaerts fastballs predominately middle and middle-away. He slugged .595 on fastballs during this time. Now let’s look at his August heat map.
Location of Fastballs Seen, August
Some of it looks similar. Pitchers are still throwing him middle and middle-away, but there are two boxes on the inner-half that are more red than before. The percentage of pitches seen in that location jumped from 8.6% in April-July to 14.3% in August. Bogaert’s slugged .465 on fastballs in August, which isn’t by any means terrible, but it’s still 130 points lower than April-July which may help explain his downward regression in batting statistics.
Note- I began working on this article yesterday before Bogaerts did this to a (0-2!) middle-in fastball:
Funny how that works.