Sheets leaves game with strained right groin
In the bottom of the third, Sheets reached down to tag out Ryan Theriot at third base after the Cubs player tried to advance on an overthrow.
Sheets gave up four hits and no runs on a damp, 44-degree day at Wrigley Field. The start of the game was delayed 71 minutes by rain.
Sheets has now gone four starts without a victory. His lone win came in the April 2 season opener when he threw a two-hitter against the Dodgers.
Elmer Dessens replaced Sheets to start the bottom of the fourth.
Copyright 2007 by The Associated Press