Jesus Aguilar was a big deal in the first half of the 2018 season. Him and Max Muncy were among two of the most surprising break-outs last year. Jesus started out smoking hot with a .298/.373/.621 slash line, 160 wRC+, and 24 home runs at the break which lead the league at the time. The 28 year old 1st baseman went on to win the fan vote with the help of the creative “Believe in Jesus” slogan.
While Aguilar enjoyed a stellar first half, his second half had much to be desired from. Lucky for him he did not receive too much attention on his 2nd half decline due to a historically good 2nd half the MVP Christian Yelich was having. That being said, regression was imminent from some peripherals in the first half. To begin here just some simple baseline 1st vs 2nd half comparisons.
From this it simply appears he is subject to a lower BABIP and less home runs. His strikeout and walk rates are similar and even in the 2nd half his wRC+ is on the right side of 100. Lets take a look at his plate discipline numbers between the 2 halves:
His plate discipline numbers look to backup the fact that his approach did not change much between the two halves. He was swinging about the same percent of the time. The only noticeable differences were that he was making contact in the zone about 6 percentage less and his first pitch strike percentage was down about 7 percentage points. As for what pitchers threw him, it was nearly the same both halves. He saw slightly less fastballs but as for pitch selection it was pretty similar. During a slump right after the All-star break Aguilar had this to say:
“I’m missing pitches right in the middle. That’s all on me. That’s all me,” he said. “But those things are going to happen. They pitch good, too. I’m not seeing anything different. I’m just missing my pitches.”
Aguilar is was correct. The pitches he was seeing after the break were not much different. As for location, here are two heat maps from Baseball Savant displaying 1st and 2nd half distributions:
Here’s something! Pitchers starting elevating the ball more one him and throwing more outside. Remember as a kid when coaches always told you as a pitcher to keep the ball low? In today’s game where the players are trying to elevate the ball and have uppercut swings it is more beneficial for a hard throwing pitcher to keep the ball up in the zone. The way pitchers were throwing to him in the 2nd half we were seeing way more of this
than we were of this
In the first half he was hitting the ball about 2 mph harder than after the mid-summer classic but an even bigger difference was that his average launch angle was about 4 degrees higher!
We could go on with almost every player nit picking every little thing between first and second halves. With Aguilar he had such a torrid first half that simply an average second half appeared to be a disappointment. He ended the season with a 3.1 WAR, and while he was not the best defensive first-baseman the league has ever seen he could provide enough offensive production to dismiss the sub par fielding. Looking ahead, Aguilar will not be the player he was in the first half of last season just as Yelich will likely not be the same player he was in the 2nd half of last season. Steamer projects Aguilar to hit .242/.317/.539 with 29 home runs in 2019. No doubt the power is legit, but hitting around .300 should not be expected of him. I wouldn’t say that a resurrection is necessary for Jesus. It is more the fact that he was performing a miracle in the first half of last season.