With two outs in the second inning and Jhonny Peralta on first base, Randal Grichuk drilled a triple into the right-center field gap for a 1-0 lead. Mark Ellis, who went 3-for-4, followed with a double to left-center to make it 2-0.
Both Grichuk (.167) and Ellis (.143) entered hitting well below .200.
St. Louis stretched the lead to 3-0 in the third as Matt Adams doubled home Matt Holiday.
The Cubs pulled within 3-2 in the fourth with some clutch two-out hitting. With one out, Ryan Kalish singled and John Baker walked. After a groundout moved the runners to second and third, Cubs starter Jason Hammel singled to right to drive in both.
Molina’s go-ahead single to center came on the sixth pitch of the at-bat from Randon.
“I thought I made a good pitch today, but something happened,” Randon said.
Molina seemed more relieved that the wild pitch wasn’t a factor than he drove in the game-deciding runs.
“(Molina) does a good job of not wearing his emotions and how frustrating that is for him,” Matheny said. “It’s hard to count the number of balls he keeps in front of him, the number of runs he saves. It’s something we don’t take for granted.”
Valbuena doubled in a run with two outs in the ninth to make it 5-4, but Rosenthal got Anthony Rizzo to ground out to end the game.
“Guys kept grinding it out,” Cubs manager Rick Renteria said. “We just fell a little short.”