The Cardinals won the opener, 8-4, in 11 innings on Matt Carpenter's grand slam.
St. Louis scored three times in the first inning of the nightcap.
After Fowler and Garcia hit back-to-back singles, Matt Carpenter plated a run with a groundout and Stephen Piscotty hit an RBI sacrifice fly. Randal Grichuk followed with an infield single and scored on Matt Adams' opposite-field double into the left field corner.
Fowler added a solo home run, his third of the season, in the second inning. Matt Adams had an RBI single in the third. Piscotty had an RBI fielder's choice in the fourth to make it 6-0.
Adam Wainwright (2-3) got the win in the nightcap while Matt Bowman (1-0) won the opener.
Ryan Tepera (1-1) and Casey Lawrence (0-3) took the losses.
