"Yesterday was the first time he felt it," manager Bob Melvin said (MLB.com). "He came in today and it was sore again. Probably the prudent thing to do is not push him too much here and give him these 15 days off and see where we go from there. But to be able to have a guy like Tommy Milone to call on and pitch tomorrow is quite the luxury."
As can be seen from the quote, Milone will take Colon's spot in the rotation.
Colon, 40, is 14-5 with a 2.97 ERA, 1.19 WHIP and 83 strikeouts in 154 1/3 innings. He made the All-Star team for the third time this season, his first All-Star trip since 2005, the year he won the AL Cy Young.
The groin issue appears to have been affecting him of late, as he has a 13.50 ERA in his last two starts.
Milone, 26, is 9-9 with a 4.39 ERA, 1.29 WHIP and 100 strikeouts in 133 1/3 innings. He was demoted to Triple-A Sacramento earlier this month where he's worked 10 1/3 innings with a 1.74 ERA in two starts.