What It Means:

The inflammation is specifically a rotator cuff injury. Rosenthal's most recent outing came on Friday -- he walked three batters -- and he hasn't shown any signs of being able to right the ship since losing his gig as the team's closer. He owns a poor 5.13 ERA and a 2.04 WHIP (33 1/3 innings) that is worst among relievers this season. It's unknown exactly how long Rosenthal will be sidelined, but he was already demoted to pitching in low-leverage situations. It's likely the Cardinals try and attack the trade market for bullpen help prior to the August 1 deadline.

Rosenthal's 4.01 xFIP is better than his ERA, but still a poor total. The one bright side is his 28.74 strikeout percentage is well above the league average (21.00 percent). Our models currently project him to record a 3.88 ERA and a 24.17 strikeout percentage over the rest of the season, pending the severity of his injury.