Rosenthal, 26, shares traits both Wong and Grichuk had before their demotions. The team isn’t sure how to get him the innings he needs to get right — like Wong with at-bats — and there could be some mechanical flaws to correct, as there were with Grichuk.

“I think any time a guy starts to struggle there’s a process,” Matheny said. “The first thing you do is maybe move them into a less high-leverage position. And then you start making alterations and do whatever you can to help them get right. Sometimes one little thing might make it click. It’s hard to explain. Kolten didn’t look right, and the first day he goes to Triple-A he barely gets to Memphis and has two home runs under his belt. Sometimes just a different atmosphere helps.

“And with Randal,” Matheny continued, “there was some obvious things he felt he could work on at the Triple-A level that he couldn’t do while he was trying to compete at the big-league level.”

With other pitchers, the Cardinals have discussed moving them to Class AAA to get needed and scheduled work on the mound without the games counting against the major-league standings.