5 MLB Pitchers Who Have Taken a Huge Step Back in 2017

Julio Teheran, SP, Atlanta Braves

What is Julio Teheran to the Atlanta Braves?

Between 2013 and 2014, he looked like a building block for the team's future rotation, as he won 28 total games with a 3.03 ERA, 3.61 SIERA, 21.5% strikeout rate, and 5.8% walk rate. And although he still won 11 games for Atlanta in 2015, the 1.1 fWAR he produced paled in comparison to the two consecutive years of at least 2.5 he had just enjoyed.

That also began the trade rumors, which haven't actually stopped. And it makes sense -- he's a 26-year-old who's shown flashes of being a productive big-league starter. Who wouldn't want to buy low on that kind of player?

Teheran rebounded in 2016 and looked more like the 2013-14 version of himself. He posted a 3.21 ERA with a 3.93 SIERA, 22.0% strikeout rate, and 5.4% walk rate. But after seemingly cementing himself as part of the Braves' future, he's gone out and struggled through another rough campaign in 2017.

Through 150.2 innings of work, the right-hander owns a 4.87 SIERA that's right in line with his 4.90 ERA. He's also added in a declining strikeout rate (18.4%) and walk rate (8.6%), while his 9.3% swinging-strike rate is on track to be under 10.0% for the first time since 2012. While Teheran has struggled at SunTrust Park this year -- his ERA at home (6.54) is over three full runs higher than it is on the road (3.24) -- the overarching issue is that he's allowing a ton of homers.

Entering 2017 (which is a sample size of 821.1 innings), Teheran was allowing 1.06 homers per nine innings, but that number has jumped up to 1.73 this year. Something that can be put on his to-do list is getting his curveball and changeup back on track. After allowing an ISO of .189 and .125 in 2016 on those offerings, respectively, those numbers have increased to .243 and .245.