Cardinals rookie reliever Trevor Rosenthal has been able to re-establish his role in the eighth inning by no longer being anxious about fulfilling his role in the eighth inning. “Early on it was definitely something that I was excited about, having a role where I could make a difference in some close ballgames,” Rosenthal said. “I’ve kind of gone back to now just when the phone rings, I go in there and get outs. I’m going to stay there from this point on.” Rosenthal, 22, has been allowed to pitch through his April struggles while maintaining a hold on the role he had going into a season, a luxury a few other relievers were not afforded. The payoff has been a reversal of results and a series of strong outings. It took Rosenthal seven pitches to retire all three batters he faced Wednesday to help the Cardinals in their 4-2 victory. The perfect eighth earned him his seventh hold of the season. The hard-throwing righty had only two pitches touch 97 mph, but he had better location than the first three weeks of the season when he only went once with back-to-back scoreless appearances. Rosenthal has struck out three of the last seven hitters he has faced, and his ERA has dropped from 5.00 to 3.45 with one run allowed in seven appearances (6 2/3 innings). “He looks like the same guy we saw last season,” manager Mike Matheny said. “He’s not trying to over-think. I think he fell into that trap of using starter stuff coming in for short stints.” CHANGE FOR GOOD Current closer Edward Mujica converted his sixth save Wednesday by pitching around a solo homer to secure the Cardinals’ victory. He did it again by liberally using his split-change, an off-speed pitch that has the deception of a changeup and the dive of a split-finger fastball. It’s a pitch that he’s thrown more than half the time this season. Before coming to the Cardinals fewer than two of every five pitches he threw was a split-change. “I think Edward has a very, very good changeup,” Matheny said. “It’s a great pitch. It’s the most underrated pitch in baseball, especially when you start talking to kids. Guys that master that pitch – it’s a very, very effective pitch. (Mujica’s) has enough depth that it can be a swing-and-miss pitch.”