Tim Wallach hit a two-run homer and Tim Raines and Andre Dawson added bases-empty homers as Montreal beat Pittsburgh at Three Rivers Stadium to give Steve Rogers his eighth victory.
Rogers (8-3) worked 6 1/3 innings but was lifted after giving up two runs in the seventh. Jeff Reardon pitched the final two innings for his eighth save.
The Expos took a 2-0 lead against Larry McWilliams (7-4) when Raines led off the third with his third homer of the season and Dawson followed an out later with his 10th homer.
"I changed my stance a little again today, for about the 15th time this year," said Raines.
"It felt real good hitting the home run right-handed, because I'm not swinging the bat well from the right side," he said.
Earlier in the day, the Pirates announced they had traded catcher Junior Ortiz and minor league pitcher Art Ray, assigned to the Class A Alexandria Dukes, to the New York Mets for outfielder Marvell Wynne and right-handed pitcher Steve Senteney.
Ray, a 25-year-old right-hander, was 4-2 with a 4.62 ERA through June 2 with Alexandria of the Carolina League; he will be assigned to a Mets' minor league squad.