Mike Trout: Reasons for Caution

A couple of days ago, I used comparable players to show how much regression should be expected from Mike Trout. Today, I am going to dive into Trout’s numbers from last season and see if any red flags exist.

Batting Average
2012 Value: .326

An AVG is driven by two components, BABIP and strikeouts. The 21-year-old’s BABIP was the third highest value in the majors at .383. By looking at his batted ball profile, his xBABIP stood at .356 or about 30 lower than his BABIP. Trout was a little lucky with balls in play over the course of last season.

Besides his full season luck, Trout saw less of the balls he put into play go for hits as the season progressed. Through July 31st, Trout had .353 AVG and a .402 BABIP. Over the rest of the season, he hit .287 with a .353 BABIP. The reason behind the drop in BABIP was that he quit hitting line drives and instead started hitting ground balls

The drop off in BAPIP, and therefore AVG, could be for several reasons. First, he could have tired as the season dragged on. He is young and it is long season.

Also, pitchers and fielders would have more information on him such as what pitches he struggles with (split finger fastballs for the few he saw) and location (inside pitches). Here is his Run Value heat map from the 2012 season (umpires perspective). The right-handed Trout is above or at league average on all pitch locations except inside pitches.

The interesting part is that pitchers didn’t attack the inside pitch as the season went on. Instead, pitchers pitched Trout higher and more outside.

Pitches in the top half of the strike zone
Mar through July: 49.9%
Aug through Oct: 54.8%

Pitches on outer half of the plate
Mar through July: 49.8%
Aug through Oct: 52.6%

Besides going up and outside to Trout, the pitches he saw changed. Downward breaking balls (change, curve and 2-finger fastball) were thrown to him less and cutters and four-finger fastballs were thrown to him more.

Mar through July 16.4% 7.8% 6.8% 15.9% 9.7% 0.7% 4.6% 38.1%
Aug through Oct 11.0% 7.3% 6.5% 15.6% 9.8% 1.7% 7.0% 41.1%
Change -5.4% -0.5% -0.3% -0.3% 0.2% 1.0% 2.4% 3.0%

Usually downward breaking balls will induce more ground balls. This generalization was not the case with Trout because as the number of sinking pitches he saw decreased, the number of ground balls he hit increased.

Finally, he could have been hampered by a left knee contusion he suffered on July 29th. Usually, an injury brings down a player’s power, but it may have caused Trout to alter his approach and hit more ground balls. I looked to see if his swing changed from before the injury to after it. Here are 4 .gifs of his swing throughout the season.

His 1st Game in 2012

Game Before Injury

Game After Returning From Injury

Last day of the season

Looking at the videos at regular speed and frame-by-frame in a .gif viewer, I could not find any change in his swing because of the knee injury.

Besides the pitches having a possible effect on Trout’s batted balls, they also affected his plate discipline over the course of the season. His K% was 19.5% before the injury and then it jumped to 24.9%. On the other hand, his non-intentional walk rate dropped from 8.4% to 11.9%. A 5% increase in a strikeout rate would put a drag on anyone’s AVG.

Home Runs/Power
2012 Values 30 HR/.238 ISO

As whole, Mike Trout displayed more HR power as the season progressed when looking at his HR/FB%.

Month: HR/FB%
May: 15.6%
Jun: 12.5%
Jul: 31.3%
Aug: 29.2%
Sept/Oct: 20.0%

Besides the HR/FB%, his batted ball distance on fly balls and home runs increased over the last couple of months.

Mar through July: 280 ft
Aug through Oct: 288 ft

His ISO, on the other hand, went in the opposite direction

May: 0.231
Jun: 0.159
Jul: 0.412
Aug: 0.216
Sept/Oct: 0.211

The late season ISO drop should be expected considering how his batted ball distribution changed from fly balls and line drives to ground balls.

With the few number of fly balls Trout was able to hit over the last couple of months, more of them went for home runs. From the beginning of the season until the end of July, he hit a HR for every 20 PA. The value increased to 22 PA for every HR from the 1st of August onward. With an almost 10 percentage point drop in FB%, I was amazed he kept the HR rate up.

I don’t see as much HR variability as I saw with his AVG.

Stolen Bases
2012 Values 49 SB, 5 CS

Trout is still young, so I expect no decline from aging. Splitting out the season before and after the knee injury, he stole bases in 8.4% of his PA before the injury and 6.7% after it. Since he was on base less in the second half of the season, the SB numbers should be expect to drop some.

The big hit to Trout’s SB numbers looks to be from a possible move from the lead off spot to the 3rd spot in the Angels’ lineup. It seems intuitive that he would attempt less SB with the power of the lineup up next. I went and looked at a few players (*) that split a season hitting either 1st or 3rd. I equalized the plate appearances and found the move to the 3rd spot didn’t hurt the player’s SB values, but actually helped. Adjusted for 600 PA in the lead off spot, the players attempted 34.8 SB and were successful 25.9 times for a 74% success rate. When the players batted 3rd, they attempted 36.0 SB and were successful 29.4 times for a 81.6% success rate. The players don’t really get the brakes put on and since they aren’t expected to steal in the 3 hole. Also, their success rate increases.


The key for projecting Trout in 2013 comes down to possible reasons for the late season drop off. If a person believes the drop off was because the season wore on him (I don’t at all), then great. He should have more experience and conditioning and be ready for a fruitful 2013.

If the injury was the problem, he should be expected to perform better in 2013 than in 2012. Yes I said it, better. If he was able to maintain what he did in the first 3 months over the course of a season, he should be expected to have a better AVG and more HR and SB. If the knee was bothering him, Trout should be the slam dunk #1 pick.

I am not buying the knee injury. Usually power drops off because of an injury. After the injury, Trout hit fly balls which went further and for more home runs than before. He was able to maintain the same swing before and after the injury. He only missed one game. Even though the time of his drop off and injury coincide, I just don’t believe his decline came because of the injury.

I believe opposing team in the league adjusted to Trout. They pitched him so he would hit less line drives and fly balls. Also, they began to strike him out more. Defensive began to get better data on where to position their outfielders. He put less balls in play and those in play were more likely to be ground balls. He will still be a good hitter if he puts up numbers similar to his August to October slash line of .287/.383/.500. The second line put him in the range of hitters like David Wright, Billy Butler, and Carlos Gonzalez instead of with Miguel Cabrera and Ryan Braun. Good hitter, not great hitters.

Trout will need to adapt like the league did to him. Early in the season, I would watch his batted ball mix. Is it closer to 55%/28%/17% GB/FB/LD like he hit over the last couple of months or near 40%/35%/25% when he was hitting the leather off the ball? Also, where is his strikeout rate? Down near 20%. Good. Up near 25%. Bad.

Finally, maybe the best method is to roll the dice and go with his projection.

I hope the preceding was detailed enough. The biggest question mark for Trout is if he will hit like he did in his first 3 months, last 2 months or somewhere in between. In re-draft leagues, I would not take him ahead of Cabrera or Braun. Both have longer established careers and therefore less down side. Trout could carry a team, but he could also perform like players taken 3-4 rounds later.
* Hanley Rameriz (2007,2010), Alex Gordon (2012), Carlos Beltran (1999,2001), Andrew McCutchen (2010,2011), Ichiro Suzuki (2012), Carl Crawford (2006), Jose Reyes (2012)

Jeff, one of the authors of the fantasy baseball guide,The Process, writes for RotoGraphs, The Hardball Times, Rotowire, Baseball America, and BaseballHQ. He has been nominated for two SABR Analytics Research Award for Contemporary Analysis and won it in 2013 in tandem with Bill Petti. He has won four FSWA Awards including on for his Mining the News series. He's won Tout Wars three times, LABR once, and got his first NFBC Main Event win in 2021. Follow him on Twitter @jeffwzimmerman.

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Jon Roegele
9 years ago

Really excellent, thorough work Jeff, thank you.

I found the move from 1st-to-3rd in the order not affecting SB attempts a very surprising finding. Scoscia will no doubt have everyone run anyway, so this could be the same for Trout if he moves to 3rd also.

I remember in August when Trout was above .330 AVG and .400 OBP with a K% above 20% looking at historical comparables, and there are not surprisingly a very small number of players who managed either of those percentages with that high of a K% in a season. Thanks for pointing out the drop over the season.