Rosenthal's walks-per-nine-innings ratio (5.4) was a concern, as was the fact that he allowed 39 percent of the first batters he faced to reach over the course of the season. With season-long command issues, Rosenthal only was able to make six appearances after May in which he did not allow a baserunner.
"That's personally a main focus for 2015, attacking hitters, trying to be more efficient," Rosenthal said. "Just at times not trying to give up the big hit too early, and not being completely confident ... trying to be too fine, might be the issue. Definitely trying to attack hitters and not fall behind early in the count is important. … Not to say that it's an easy thing to do."
The Cardinals learned throughout the season that they have to guard against becoming over-reliant on Rosenthal in order to keep the 24-year-old fresh. With Jordan Walden, who has previous closing experience, now in the bullpen, the Cardinals have another viable ninth-inning option should Rosenthal need to rest.
"Talk about a character test," manager Mike Matheny said of Rosenthal's season. "What he was put in night in and night out, the ups and downs, and even how the fans responded at times, he just kept his head down and kept going. He ended up having a terrific year. He was really, really tested."
Getting repeated years of success from a closer is something the Cardinals have been seeking for awhile. Should Rosenthal be able to keep the reins of this role, it will mark the first time since 2010 that the incumbent closer will finish a second straight season with the job. Ryan Franklin (2008-10) was the last pitcher to lead the Cardinals in saves in consecutive seasons.
"For me, the goal is always to take care of myself and try and be out there every day," Rosenthal said. "I'll give it my best effort every time out there, so as long as I can do the little things to make myself available to pitch."
Jenifer Langosch is a reporter for MLB.com. Read her blog, By Gosh, It's Langosch, and follow her on Twitter @LangoschMLB. This story was not subject to the approval of Major League Baseball or its clubs.