The right-hander threw a pitch to Colorado's Todd Helton and immediately grimaced in pain. After meeting on the mound for a couple minutes with the head trainer and manager Ned Yost, Sheets was removed from the game with the Rockies leading 1-to-nothing.
Sheets was pulling on the top of the middle finger before leaving the field. The team said he would undergo an M-R-I on Monday if the finger still bothers him.
Sheets was replaced by rookie Yovani Gallardo.
Tony Graffanino provided the late-game heroics today, singling in the winning run in the bottom of the tenth to lead Milwaukee over Colorado 2-to-1.
Derrick Turnbow pitched a scoreless tenth for the victory, improving to 2-and-3.
The Brewers managed only four hits while Colorado had only three.