“Playing every day and your confidence comes back,” Diaz said.

“Diaz is another guy that we have seen bits and pieces of,” Matheny said. “He looks like an overall different player. His arm is healthy. You could tell that he was still trying to get that right. You see more confidence. You see it the way Diaz is going about it. It’s how they’re supposed to go down (to the minors) and prove.”

Peralta, who will turn 34 in May, is entering the third year of a five-year, $53 million deal. In the first two years he has been one of the most productive shortstops in the majors, second only to Troy Tulowitzki in terms of slugging.

Peralta wore down in the second half of 2015 and saw his extra-base thump erode. That led him to alter his workouts this winter, increase his length strength, and reduce his weight through a better diet. The injury was a fluke – but it’s one the Cardinals are familiar with.

Catcher Yadier Molina had two operations this past winter to repair a torn ligament like Peralta’s in his left thumb. Molina is expected to start swinging a bat for the first time this week.

Strength takes time to recover and will determine the length of Peralta’s absence.