St. Louis homered twice for the second straight game and will go for a sweep of the three-game series behind 12-game winner Kyle Lohse on Thursday night.
The Cardinals have dominated the season series regardless of who’s been on the mound. They are 4-0 against the Diamondbacks this year.
Behind HRs from Holliday & Jay, St. Louis tops Arizona 8-2.
Pinch hitter Matt Carpenter lined a go-ahead double in the sixth inning, Allen Craig homered to cap a four-run burst in the ninth.
Carlos Beltran hit a 2-run homer off Ian Kennedy in the first, then cleared the bases with a shot in the second for his 10th career grand slam.
Jake Westbrook is 3-0 with a 0.86 ERA in starts against teams other than the Pirates this season.