The 27-year-old right-hander credits the return to form primarily to comfort. During his stint in the Minors, Salas passed a kidney stone that had been bothering him since December. While a doctor had identified the issue over the winter, Salas didn't necessarily understand the effect it was having on his performance earlier this year, because there wasn't much specific pain.
All Salas knew was that he didn't feel right.
But since returning from a May demotion to Triple-A, Salas has made five scoreless appearances. He allowed two baserunners in his first four innings and then worked around two hits and two walks in a two-inning outing in Sunday's extra-innings affair against the Royals.
The success is largely the result of crisper movement on Salas' fastball.
"I could pitch, but I didn't feel 100 percent," Salas said before Sunday's I-70 series finale against Kansas City. "I would throw a fastball and it would be flat. It had no life. I said, 'I don't know what's happening.' I didn't have any pain in my arm, but my fastball was flat. I didn't feel aggressive. I wanted to try, but my body wasn't working. But after my kidney stone [passed], when I woke up, I felt more and more energy. I'm more excited to play."
The energy, Salas explained, is particularly a welcome return. He said that there were times earlier this season that he'd be sitting in the bullpen feeling like he was going to fall asleep. Salas couldn't pinpoint the reason for such fatigue.
"I didn't know what was happening," Salas said. "I was not myself. I didn't feel aggressive. Now I feel much better. I'm feeling good."
The Cardinals entered the season anticipating that Salas would be one of the team's key late-inning relievers. If Salas can show enough consistency to move back into such a role, that could go a long way in helping settle a bullpen that still has several pitchers trying to solidify roles.
"It looks to me like he's finishing his pitches," manager Mike Matheny said. "There was definitely something going wrong before. We couldn't put our finger on it. He's making pitches now. He has to locate his fastball, and he has to have enough on his fastball to make his changeup good. That's what he's doing now."