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Julio Teherán is really struggling

Teherán’s velocity drop and lack of changeup effectiveness are starting to catch up with him.

Toronto Blue Jays v Atlanta Braves Photo by Scott Cunningham/Getty Images

A few months ago I wrote about Julio Teherán having a very good 2016 season despite a decline in fastball velocity. In that article, I cited one from FanGraphs’ Eric Longenhagen analyzing the lack of effectiveness of Teherán’s fastball and changeup, the latter of which used to be his best secondary offering.

Last year, Teherán had a 3.35 RA9 and 4.8 bWAR. In my previous article, I mentioned concern about his future performance because even though he was very successful in 2016, his stuff belied his performance. Well, we are only two months into the season, and it looks like those concerns were well-founded.

So far this season, Teherán has been a replacement-level player. He has a poor 5.69 RA9, and compared to last year, his strikeout rate is down 22 percent while his walk rate has nearly doubled. He has been a bit homer-prone, too, and that is without an exorbitantly high HR/FB ratio.

I wish I could say that Teherán is suffering from a lot of bad luck, but that just does not seem to be the case. His BABIP is more or less in line with his career rate. I can say that his strand rate is a bit low, and his infield hit percentage is over double his career rate. That might be a function of bad luck, though it could also be a failure of the infield defense. I can only speculate. Regardless, an increase in infield hits is not going to cause a pitcher’s run average to skyrocket. Teherán’s DRA is roughly the same as his RA9, so there are no answers there either.

According to Brooks Baseball, Teherán’s velocity on his four-seamer is only slightly lower than last year, and the average velocity of his other pitchers are roughly the same, so it’s not a velocity issue. The movement on his pitches are more or less the same, too. His four-seamer appears to have lost a bit of life to it, but it has not had any detrimental effects on his performance yet. It appears roughly the same, minus some BABIP help.

Teherán’s four-seamer

AVG SLG BABIP
AVG SLG BABIP
2016 .245 .402 .286
2017 .215 .327 .244
Brooks Baseball

One significant change is with his slider, a mediocre pitch that is effective because of his command of it. Well, that command has not plummeted, but it has diminished, though it still appears to be quite good.

2016 vs. 2017 Slider Command
Brooks Baseball

If anything, the improved performance against Teherán’s slider looks to be more BABIP luck than anything. That should improve in time. Furthermore, the whiff percentage on the pitch is almost 16 percent! Although that is down significantly from last year, it is still very good.

Teherán’s slider

AVG SLG BABIP
AVG SLG BABIP
2016 .185 .327 .265
2017 .246 .368 .324
Brooks Baseball

Teherán’s woes appear to be coming from his changeup. Last year, his once-great changeup had diminished to something that was thrown just to give hitters something else to look at, otherwise known as a “show me” pitch. It worked, too, but that was a result of a .217 BABIP. Now, hitters are teeing off on it. They are hitting .379 with a whopping .690 SLG. Even with a .360 BABIP, those numbers are striking. It might be time for him to scrap the pitch.

One area of note where Teherán is suffering from some bad luck is with his sinker. He only throws it 12.5 percent of the time, but he has given up two homers off it with a HR/FB ratio of 18 percent. His 48 percent ground ball rate on the pitch is pretty good. All of that is to say his sinker should be better going forward.

Brooks Baseball shows that, aside from his changeup, Teherán is not pitching too differently than last year, but his results are terrible. Dropping the problematic cambio should help, but I can’t pretend to know what his true talent is going to be. It definitely is not his 3.35 RA9 from last year, nor is it his current 5.69 RA9. ZiPS projects it at a 4.37 RA9, which sounds far more reasonable.

It is tough to make out what Teherán is right now. A full 2017 season of data should help clear that up. It is going to hurt if he turns out to be nothing more than a back-end starter, because the Braves hung on to him during their rebuild in hopes that he would anchor the starting rotation once the team becomes competitive again. The Braves do have some interesting pitching prospects in their excellent farm system, so all is not lost with the starting rotation’s future if Teherán does not improve.

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Luis Torres is a Featured Writer at Beyond the Box Score. He is a medicinal chemist by day, baseball analyst by night. You can follow him on Twitter at @Chemtorres21.