The Giants recalled Winn from Triple-A Sacramento on Monday.
Winn has made nine of his 12 appearances with Sacramento this season as a starter, but he's expected to operate as a multi-inning option out of the bullpen during his upcoming stint with the big club. After being added to the Giants' 40-man roster over the winter, the 25-year-old right-hander submitted a 4.35 ERA and 1.65 WHIP while striking out 51 over 41.1 innings at Sacramento to earn his first call to the majors.