MINNEAPOLIS -- Left-hander Pedro Hernandez left Friday's 16-5 loss against the Mets in the sixth inning with a left calf strain. He's day-to-day.
Hernandez, who was pitching in long relief of starter Vance Worley, threw four pitches to Ike Davis with one out in the sixth before coming out of the game in the middle of the at-bat. He threw a warmup pitch to see if he still felt discomfort and the decision was made to take him out for reliever Ryan Pressly.
"It was something in his calf, but I don't think it was bad," Twins manager Ron Gardenhire said. "We'll wait until the morning and see how everything is. We need to make a roster move to activate Diamond, so we're going to wait and see what we have to do."
Hernandez tossed 4 1/3 innings, allowing one run on four hits. But one of those hits was a big one, as he gave up a grand slam to John Buck with nobody out in the second inning after Worley loaded the bases.
Hernandez, who made a spot start against the Orioles on Sunday, is a candidate to be either placed on the 15-day disabled list or optioned to Triple-A Rochester on Saturday, as the Twins have to make room for left-hander Scott Diamond, who is set to come off the 15-day disabled list on Saturday to start against the Mets.
Rhett Bollinger is a reporter for MLB.com. Read his blog, Bollinger Beat, and follow him on Twitter @RhettBollinger. This story was not subject to the approval of Major League Baseball or its clubs.