Jesus Aguilar and Eric Thames have both found their place in Milwaukee after taking very different paths to the roster. While Aguilar has cemented himself in the middle of the lineup, Thames struggles to stay relevant. BREW MATHs uses Sabermetrics & high-yield graphics to break down every sinewy pound…

Weighted on base average (wOBA) is a great metric to use as a measure of a hitter’s overall performance. It attempts to assign value to all the things a hitter can do and then turns it into a recognizable number. This graph shows how Aguilar and Thames compare to the MLB Average in regards to wOBA:

When a player is coming off the bench (as ET has), their numbers should be taken with a grain of salt. On that note, we will spend a lot more time on Aguilar since he dominates the playing time.

BASEBALL BIO

The 28-year-old Jesus Aguilar is from Venezuela and was signed as an amateur free agent by Cleveland in 2007. He ended up bouncing around their farm system until Milwaukee signed him away in 2017. He will be eligible for arbitration next year but in the mean time he is an excellent value at just above the league minimum. Aguilar is under team control until 2023 when he is scheduled to become a free agent.

The average MLB salary for first baseman is $4.36M. Last year Aguilar made $557,200.

If Aguilar is able to sustain his current production at the plate he will be in line for a massive raise.

PLATE PRODUCTION

(NOTE: All of the metrics that appear in our analysis are summarized in straightforward manner at the website: http://www.brewmaths.com under ‘THE MATHs’ Menu in website header)

While this graph is somewhat busy, it is that way by design… All of the metrics here are good indicators of overall plate production. Aguilar’s stats here are as steady as they come. He is consistent and more importantly… consistently playing at a high level:

wOBA: 0.374 (17th, MLB)/ BABIP: 0.309 (Above Average) / OBP: 0.352 (45th, MLB)

There are multiple things we can take away from this large sample size:

• His BABIP (GOLD LINE) is relatively stable throughout his career. While it goes as high as 0.353 and as low as 0.213, it ends up balancing at a 0.315 career mark. That is above average and implies that Aguilar may be able to sustain his current pace.
• The On-base percentage is impressive considering he is a true power hitter with a high Swing% rate.
• His wOBA is approaching elite level and that probably is the best single stat a hitter could excel in. It is currently on a slight rise as his BABIP declines. This typically means that he is on a ‘unlucky streak’ which is hard to believe. That said, Miller Park is the second friendliest hitter’s park in The MLB.
• We may not have seen Jesus at the peak of his powers yet. The graph above suggests it is possible for Aguilar to improve upon the already impressive 0.274 / 35 / 108 of 2018 (but something comparable to that is more likely).

POWER

• Slugging percentage is on a steady rise since 2014 (AAA) with no slowing down in sight. It is simply (TB / AB) and tells us when he hits the ball it does damage via extra bases.
• ISO is a measure of raw power and follows the same upward slope we see with slugging percentage. When we see them both rise we know a player’s power is improving without sacrificing his batting average.
  • AVG is included here to illustrate how it remains steady even though he is swinging harder and making better contact. Understanding what happens when he hits the ball would help us clarify this.

BATTED BALL STATISTICS

While home runs / fly ball (HR/FB) is traditionally thought of as a pitching metric, over a large sample size, it can help us understand changes in a hitter’s approach. The same can be said for line drives percentage represented here, too:

This is more relevant than one might think and the following FanGraphs Chart summarizes why concisely…

Jesus Aguilar is making progressively better contact each year. The harder hit balls then have a greater chance to fall for a hit and when they do, lead to more bases. This is especially relevant in our analysis of Aguilar since he is a known “swinger”:

Almost anywhere you pitch to Zeus other than the corners, he is hacking. He also strays away from inside pitches but is very aggressive overall. Aguilar has a talented enough bat that he can ‘swing away’ until he has to ‘shorten up’ with two strikes. Aguilar is notoriously a good “two strike hitter” and was near the league lead in that category for most of the year.

RATE STATS

• Aguilar does strike out at a high rate which is typically the cost of power. However, he is disciplined enough that the walk rate is also high.
• Strikeouts are trending down (in the face of a large sample size and in hitter friendly park)
• Walks are trending up and reinforce the idea that Aguilar is patient and has quality vision at the plate.
• If both of these trends persist Jesus would find himself in rare air… a top-notch power hitter with great vision and the ability to hit well with two strikes.
  • A look at the rate stats from a different angle shows us exactly what we would expect to see:

In his second year as a Brewer, Jesus Aguilar was:

• as aggressive as ever, swinging at the same rate as he did in year one BUT
• making more contact AND
• therefore missing less (i.e. swinging strike percentage)

We can even break this into the type of pitch he is swinging at:

INTERPRETATIONs / CONCLUSIONs

With Aguilar, we now have a large enough sample size over his career and as a Brewer to make some sense of his stats. The statistical progression we just walked through highlights multiple concrete points:

• Aguilar’s plate production is approaching the elite level and may still be improving. He could be in line for a monster year if he continues to improve upon his rate stats. Specifically, his high strike out rate, a rare weakness.
  • The high ‘K rate’ is a byproduct of an aggressive approach at the plate.
• JA’s power numbers are on the rise and have been for some time now. His BABIP of 0.316 helps us to believe that what he is doing is sustainable.
  • We likely have not seen Aguilar’s peak yet but 2018 was probably close
• Jesus is an underrated fielder… last year in 1052 innings, Aguilar made just two fielding errors and two throwing errors.
• Aguilar is a hard worker and seems to be a “lifelong learner.” He continually improves even in the face of sizable odds.
  • He has even improved in his short time as a Milwaukee Brewer,
  • He is a student of the game in the prime of his career. We get to watch him fine tune his approach on a team picked to go deep in the playoffs…
    • Is it March yet?

MOST LIKELY BACKUP: ERIC THAMES

Thames has a great deal of pop remaining in his left-handed bat and can still hit with power. His biceps tell you all you need to know. He is a decent pinch hitter but comes with a great deal of limitation. Despite being able to play first base and right field, he does not defend either position well. Thames is also very poor against left-handed pitching and has not played well on the road since becoming a Brewer. As of now, he is a situational bat who may not be on the roster opening day.

While Eric Thames is a great clubhouse presence, his production has been lagging. It is difficult to say how much of that is due to a lack of playing time and how much of it is age / deterioration of skill. However, he comes at a high price for a bench player who cannot hit left-handed pitching ($6M with a $1M dollar buyout next year). Unfortunately, the clock is ticking for Thames on a team trying to take the final step.