Analyzing the struggles for Atlanta Braves starting pitcher Julio Teheran

With one-third of the season complete, the Atlanta Braves have some interesting decisions that will arise. Of those decisions: Julio Teheran.

It’s no secret that Julio Teheran has not been the All-Star caliber pitcher that he once was for the Atlanta Braves. After his recent start in San Diego, Teheran landed on the disabled list with a right thumb contusion. This is only the second time in his career that Teheran has been on the DL. The first time was in August 2016 for a right lat strain.

I don’t think Teheran’s DL placement is a sign of being an injury prone pitcher, but rather a mosaic image of his struggles as of late.

Over his last 5 starts, Teheran has a 6.11 ERA and a 1.429 WHIP, with 15 walks and 14 strikeouts. He’s also allowing 25 hits,19 earned runs, and eight home runs.

The velocity dilemma.

Teheran’s decrease in velocity has been a known issue for a while now. A decrease in velocity can become problematic for a pitcher because modern-day hitters have become accustom to seeing fast pitches, and adjusting to slower pitches should become easier for hitters as time progresses.

Teheran’s average fastball this year is 89.48 mph while the league average is 92.93 mph. Some hitters might require just a few pitches to slow themselves down to wait back on lower velocity pitches, while other hitters may struggle more with adjusting to lower velocities.

Adjusting to slower pitches with more break can be tough for some hitters, but the decrease in velocity could, in theory, give hitters an advantage over time because it gives the hitter more time to recognize the pitch type, spin, and location.

However, a decrease in velocity often times translates to increase in the break of a pitch. The slower velocity will mean more time for hitters to adjust which can be problematic, but an increase in break backs up the issue of low velocity.

With the increase in velocity from pitchers around the league, it seems reasonable to think the Atlanta Braves will follow the high velocity evolution of baseball and acquire/utilize pitchers with high velocities.

More strikeouts and less walks is what Atlanta needs out of Teheran’s spot in the rotation, and his lack of decreased walks and increased strikeouts makes the idea of trading Teheran seem attractive.

The point I’m trying to make is that low velocities pitchers are most likely not going to make it for much longer in the major leagues, and one of those low velocity pitchers at the moment is Julio Teheran.

Teheran is struggling. So what’s wrong with Teheran, OTHER than his lack of velocity?

A Statcast look into Julio Teheran…

Teheran’s issues include: increased walks, decreased strikeouts, increased HR’s surrendered, and a lost lethality of his fastball coupled with a lack of curveball and change-up usage vs RHB with a lack of slider usage vs LHB.

Looking at his overall BB% (walk percentage), we can see significant changes. In 2015, his BB% was 8.7%, in 2016 it was 5.4%, in 2017 it was 8.9%, and now in 2018 it is 11.1%. The only time Teheran’s BB% was ever in double digits over 10% was in 2010 when he was in Double A, where his BB% was 10.5%.

From 2013 to 2016, Teheran had a K% over 20% every year. In 2013 it was 22.0%, in 2014 it was 21.0%, in 2015 it was 20.3%, and in 2016 it was 22.0%. However in 2017, Teheran’s K% dropped to 18.6%, and now in 2018, it is 18.9%. Teheran has been walking more batters and striking out less batters which is becoming a problem.

In both of Teheran’s All-Star years (2014 and 2016), he surrendered only 22 HR’s. Then in 2017, Teheran gave up 31 HR’s in 32 games and seems to be on the same path in 2018 having given up 14 HR’s through 13 games.

This increase in HR’s surrendered could be attributed to the league-wide increase in home runs, but Teheran has been leaving some of his pitches over the plate which hitters are smacking out of the park at high rates. If a pitcher makes a mistake, major league hitters will jump all over it, and maybe Teheran is making too many mistake pitches. Maybe Teheran makes more mistake pitches to RHB which is why he rarely uses his change-up or curveball vs RBH.

Every year since 2013, Teheran’s fastball has always had a K% over 20% and a BB% below 10%. In 2018, Teheran’s fastball has a 17.6 K% and a 15.2 BB%. His fastball has seen increases in wOBA, xwOBA, spin rate (good), BB% (bad), and Whiff% (good) while seeing a decrease in K%. In essence, this tells us that Teheran’s fastball has been losing its value and effectiveness despite an increase in spin rate and whiff rate.