Odubel Herrera scored the first run of the game then drove in the next.
After his leadoff single started the game on the right foot for the Phillies, the center fielder knocked his 23rd double of the season to score Andrew Knapp in the second inning.
The Cardinals trail 2-0 midway through the third.
Knapp started the second inning with a single to right field. Wainwright issued his first walk of the day to Freddy Galvis in the next at-bat. Then Phillies starter Aaron Nola -- who has allowed two hits today -- sent a grounder back up the middle.