Mujica has been impressive since taking over the closer role for St. Louis earlier this season. The right-hander owns a 2.53 ERA with 37 saves in 41 appearances. Mujica, however, has struggled during September, allowing seven runs on 15 hits over 6 2/3 innings with two blown saves.
The reliever reviewed film with Cardinals pitching coach Derek Lilliquist and found a mechanical flaw in his delivery, according to Derrick Goold of the St. Louis Post-Dispatch. Mujica thinks the flaw in his delivery is due to fatigue, telling the reporter:
"My body feels like a little bit tired, and my release point is getting a little bit up. My thinking in my mind I've set it to get to the playoffs. One more month. Right now, I don't want to think about (fatigue). Let's finish it off, these nine games, and then if we make the playoffs think about the playoffs."
The Cardinals have a few options to close out games without Mujica. The team traded for former Milwaukee Brewers closer John Axford at the end of August; he saved 105 games for Milwaukee from 2010-2012. Trevor Rosenthal has excelled as a set-up man this season, posting a 2.74 ERA with 103 strikeouts over 72 1/3 innings.