McGee (0-1, 3.27 ERA, 47 strikeouts, 12 walks in 41 1/3 innings) has operated as the primary setup man for closer Greg Holland. Righty Pat Neshek, whom the club acquired from the Phillies on Wednesday, pitched an eighth inning more suited for McGee but emerged scoreless during Saturday's 4-2 victory over the Nationals.
Even without McGee's injury, which he hopes was caught early enough to allow him to return when his time on the DL is up, the Rockies have been reportedly seeking additional bullpen help.
McGee last pitched on Tuesday, going 1 2/3 innings and taking the decision in a 3-2 loss at St.