Astros’ Jandel Gustave Undergoes Tommy John Surgery

Astros righty Jandel Gustave underwent Tommy John surgery today, writes Jake Kaplan of the Houston Chronicle. The hard-throwing reliever had been on the disabled list since April 19 with what was announced as a flexor strain. It’s not clear when the diagnosis of a torn ulnar collateral ligament was made, but regardless, Gustave will be out for the rest of the 2017 campaign and likely most of the 2018 season as well.

[Related: Houston Astros depth chart]

Gustave, 24, was picked out of the Astros’ organization in the 2014 Rule 5 Draft by the Red Sox and bounced around the waiver circuit during Spring Training 2015 before being returned to Houston in early April. He made his MLB debut a year later in 2016, tossing 15 1/3 innings of 3.52 ERA ball with a 16-to-4 K/BB ratio and a 40 percent ground-ball rate. This year, Gustave made the Opening Day roster out of Spring Training for the first time in his career and tossed five innings with the ’Stros before falling to injury. In that brief time, he issued seven walks and fanned just two men.

The Astros have solid bullpen depth as it is, and currently rank 11th, third, and first in the league, respectively, in bullpen ERA (3.85), FIP (3.27) and xFIP (3.43). The loss of Gustave and departure of Luke Gregerson as a free agent this offseason will thin that depth out a bit, though the combination of Ken Giles, Chris Devenski, Will Harris and Michael Feliz make for a formidable top four in the relief corps.