Nick Vincent, Dale Thayer, Luke Gregorson and Huston Street worked an inning apiece after Volquez (7-8) faded at the end of a five-inning outing. Street was perfect in the ninth for his 16th save in 17 chances after Carlos Quentin's RBI double off Trevor Rosenthal in the ninth put the Padres up by two runs.
The Cardinals' Lance Lynn (11-5) lost for the fourth time in five starts, allowing four runs in five innings. Allen Craig had a two-run single and 29-year-old rookie Brock Peterson had an RBI groundout in his first major league at-bat after getting called up to replace injured Matt Holliday.
A sellout crowd of 45,288 showed up in 92-degree heat, enticed by Red Schoendienst replica jersey giveaways. The 90-year-old Cardinals Hall of Famer was honored with a video tribute before the third inning as he watched the game from a private box.
The Padres had nine base runners the first three innings while taking a 4-0 lead, scoring twice in the third on a run-scoring wild pitch on a 2-2 pitch against Hundley followed by Hundley's broken-bat infield hit.
Volquez retired the first nine batters in order, then allowed three runs on four hits, two walks and two wild pitches in the fourth and fifth. He lost his previous two starts and hasn't lasted longer than 5 1-3 innings his last three outings.
Lynn has been an 11-game winner prior to the All-Star break both years in the St. Louis rotation, benefiting this year from an offense averaging nearly six runs per start. He's been out of sync lately, giving up 10 runs in 9 1-3 innings his last two starts.
Notes: Adam Wainwright (12-5) goes for his league-leading 13th win in the series finale Sunday with Eric Stultz (8-7) going for the Padres. ... Cardinals outfielders combined for four sacrifice hits for the first time in franchise history Friday, two bunts by Jon Jay and two sacrifice flies by Carlos Beltran. ... Peterson led the Pacific Coast League with 22 homers.
Link to box score: San Diego 5 at St. Louis 3
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