The Pirates trailed 5-2 entering the ninth but scored four runs against reliever Nate Jones (2-1) on Elias Diaz's two-run double and Colin Moran's two-run homer, his third, to right-center.

Pittsburgh reliever Richard Rodriguez (1-1) pitched the eighth, giving up a run but still earning his first major league win, and Felipe Vazquez pitched a perfect ninth to pick up his seventh save in as many opportunities.

Jordy Mercer and Gregory Polanco hit solo homers for Pittsburgh, which has won three in a row and four of five.

Pittsburgh starter Trevor Williams had his shortest outing of the season. He allowed four runs, including two homers, and seven hits in five innings, with three strikeouts and two walks.

Chicago's Reynaldo Lopez gave up two runs and three hits, including two homers, in 7 1/3 innings, with six strikeouts and two walks.

The White Sox have lost five straight.

In the second, Tim Anderson hit a two-out, two-run homer, his seventh, to left field after Daniel Palka singled with one out for a 2-0 Chicago lead.

White Sox left fielder Nicky Delmonico exited in the fifth inning due to a bruised right quad suffered in the third when he collided with Pirates first baseman Josh Bell. Delmonico is listed as day-to-day.

In the fourth, Chicago's Welington Castillo led off with a broken-bat single and scored on Palka's homer, his third, to left-center to make it 4-0.

Pittsburgh cut the lead in half in the sixth. Mercer led off with a homer to left, his second of the season and second in three games. An out later, Polanco hit his seventh homer on a shot just inside the foul pole in right to make it 4-2.

In the eighth, Jose Rondon hit a double to left for the White Sox and scored on Castillo's double to the wall in right for a 5-2 lead.

--Field Level Media