The Cardinals had a big second inning where they scored four runs, but Adam Wainwright allowed the Giants to cut into that lead in the third.
With two outs, Wainwright gave up a single to second baseman Joe Panik and then an RBI double to third baseman Christian Arroyo. Cardinals right fielder Randal Grichuk appeared to have lost the ball in the sun for a little, and the ball rolled all the way to the warning track.
Wainwright got first baseman Brandon Belt to foul out though to keep the lead at 4-1.
Through his three innings, Wainwright has allowed just the one run on three hits with a walk and four strikeouts.