Cardinals 4, Padres 3: Jon Jay delivered a pinch-hit, two-run double in the eighth inning to snap a tie as host St. Louis held on to take the opener of the four-game series.Tony Cruz led off the frame with a single off Alex Torres (1-1) and pinch-hitter Daniel Descalso drew a walk before Matt Carpenter singled to load the bases. Nick Vincent came on and was greeted by Jay's shot to deep center field that plated two for a 4-2 lead.San Diego got back a run in the ninth on pinch-hitter Jake Goebbert's RBI single, but Alexi Amarista was thrown out at the plate on a controversial call that resulted in the ejection of Padres manager Bud Black. Trevor Rosenthal proceeded to walk Will Venable to reload the bases before striking out Tommy Medica to nail down his 36th save and make a winner of Seth Maness (4-2), who worked a perfect eighth.Jhonny Peralta belted a two-run homer and Matt Adams notched two hits for the Cardinals, who remained two games behind first-place Milwaukee in the National League Central. Jedd Gyorko and Rymer Liriano each drove in a run while Amarista collected three hits for the Padres, who had their five-game winning streak snapped and fell seven games behind St. Louis for the second wild card.St. Louis grabbed the lead in the second inning, when Adams led off with a single and Peralta followed with his 16th blast of the season. San Diego drew even in the sixth as Gyorko plated a run with a fielder's choice before Liriano singled home Medica two batters later.GAME NOTEBOOK: Black was tossed by home plate umpire Bob Davidson for arguing that Cardinals C A.J. Pierzynski blocked Amarista's path to the plate after video review upheld the out call. ... San Diego starter Eric Stults allowed two runs and four hits in seven innings while St. Louis' John Lackey yielded two runs and five hits in seven frames. ... The Cardinals posted their fifth win in seven home contests and moved one-half game ahead of Pittsburgh for the first wild-card spot in the NL.