Zach Stewart took a perfect game into the eighth inning, and the rookie right-hander ended with a one-hit shutout, as the Chicago White Sox took a 4-0 win over Minnesota in the second game of a doubleheader.
Danny Valencia fouled off three straight pitches before lining a ball into the right field corner to lead off the bottom of the eighth inning.
That was the only blemish for Stewart (2-3), who was making just his eighth career start. He struck out nine and threw 75 of his 114 pitches for strikes.
A non-roster invitee to spring training with the Blue Jays, Stewart was acquired from Toronto with right-handed pitcher Jason Frasor on July 27 in exchange for right-hander Edwin Jackson and infielder/outfielder Mark Teahen.
Brent Morel had three hits, including a two-run single. Alexei Ramirez and Alex Rios each tallied three hits and combined to score three times, as the White Sox completed a doubleheader sweep.
In the afternoon game at Target Field, Philip Humber tossed seven scoreless innings to lead the White Sox to a 2-1 victory.
Scott Diamond (1-3) was touched for eight hits and two runs over five innings in the night game for the Twins, who lost their fourth in a row.