Easy enough in theory, sure. But there was no way Rosenthal could have envisioned the game he'd be a part of Friday night.
Rosenthal and fellow rookie reliever Joe Kelly played an integral role in St. Louis' momentous comeback win in Washington, helping secure the largest comeback in a winner-take-all postseason game with a stunning 9-7 victory over the Nationals in Game 5 of the National League Division Series.
Kelly was called upon for mop-up duty after starter Adam Wainwright faltered in 2 1/3 innings, surrendering six runs on three homers. Kelly tossed 1 2/3 perfect frames, striking out two. Rosenthal followed with a perfect inning of his own, also striking out a pair of hitters.
"I went in there and was like, 'First-pitch strikes, a few ground balls and get back in there,'" Kelly said. "Got through that third inning, got those two outs, and was like, 'Just keep doing that and we have the chance to win this game.'"
The Cardinals did. And now the duo has combined for seven scoreless innings this postseason.
"We've just been feeding off the guys that have been here, the older guys and the guys that were on this team last year," Rosenthal said. "Feed off what they bring to the table and give it everything we have every day. That's really all we can do."
Manager Mike Matheny pointed to relievers like Jason Motte and Edward Mujica as mentors in the clubhouse and in the bullpen. They've helped to counsel Kelly and Rosenthal, along with the club's No. 2 prospect Shelby Miller, who was added to the postseason roster when Jaime Garcia was shut down.
"It's picked us up a ton," Motte said of the rookies' effort. "These guys have great arms down there and they have great stuff. It's not just like they're coming up and have one pitch -- a 99-mph fastball. They have great offspeed stuff and come in and mix it up."
Matheny figures he'll call on those guys at least a few more times, with the Cards advancing to their second consecutive NL Championship Series, facing the Giants in Game 1 on Sunday (7 p.m. CT on FOX) in San Francisco. And with a grueling regular-season stretch run, a one-game Wild Card playoff and a five-game Division Series under their belts, they think they're ready.
"For Joe Kelly to come in and close in a situation early in the game, and an opportunity to eat up a couple innings, and then Trevor Rosenthal to do what he did -- those are not easy situations," Matheny said.