ARLINGTON — The ankle is not directly connected to the shoulder, but in this instance, the Rangers have taken precautions to ensure that the former doesn’t impact the latter.  

The Rangers placed right-handed pitcher Jack Leiter on the 15-day injured list with a right ankle posterior impingement prior to Sunday’s series finale vs. the San Diego Padres and promoted right-handed pitcher Jose Corniell in his place. Leiter had dealt with the injury earlier this season but, according to president of baseball operations Chris Young, “it got a little worse” after he slipped on the on deck circle in an April 22 start vs. the Pittsburgh Pirates. 

“The reality is he just wasn’t able to do what he was capable of doing throughout the starts,” Rangers manager Skip Schumaker said. “It started showing up more and more, and it wasn’t fair to him that we kept sending him out there, so I think this was the right move.”

Leiter, who threw 54 2/3 innings in 10 starts after he rolled his ankle on the on-deck circle, believed that he could pitch through the injury until it reached the point where a shutdown was necessary. The Rangers continued to monitor his status, but after Leiter allowed six runs in four innings vs. the Minnesota Twins Thursday, he underwent additional scans that showed his ankle “has gotten worse” according to Young.

It’s unclear at this time how long Leiter will be sidelined for. Young said that the team’s internal data confirmed that Leiter had tweaked his mechanics and delivery because of the injury to his push-off leg, and because of how he had to compensate for it, the concern is that it could lead to an upper-body ailment. 

“It’s altering his mechanics and clearly it’s impacting his performance,” Young said. “Jack has not made it an issue and that speaks to his level of competitiveness. He’s not had excuses, but the reality is, he’s having to change his delivery to compensate for it and we cannot put him in harm’s way.”

The 26 year old has yielded a 5.43 ERA since he slipped on the on-deck circle, and in his last three starts, he posted a 9.88 ERA and was unable to pitch deep into games. His four-seam fastball command — specifically his ability to locate it up in the strike zone — has noticeably declined within the last month. Opponents hit just .194 against Leiter’s four-seam fastball prior in his first five starts this season. They hit .257 — and slugged .514 — against it since. 

Leiter was unavailable to discuss his injury before Sunday’s game. 

“I think he was doing whatever he could to make his start,” Schumaker said. “Jack is a really tough kid. The fact that he was trying to make every start dealing with his push-off leg might’ve started to impact other things, so you also have to make sure you’re doing right by the player, as much as I want him out there every fifth day. You have to make sure that he’s okay as well. He’s part of the future of our team, our franchise and I think he’s going to be pitching here a long time.”

The Rangers have not yet determined how they’ll fill Leiter’s spot in the rotation. Young said that the team will be “creative” and will likely use an opener in front of whoever starts. Corniell, the team’s fourth-ranked prospect per MLB Pipeline, had a 6.08 ERA in seven games at Triple-A Round Rock. The 22 year old last pitched June 12.