Evan Longoria's two-run, go-ahead double in the seventh inning allowed the host San Francisco Giants to survive a crazy play that saw them surrender two runs earlier in the game en route to a 6-5 win over the San Diego Padres on Tuesday night.

In the opener of a two-game series, the Giants trailed 4-3 before Brandon Belt drew a walk from the Padres' fourth pitcher, right-hander Trey Wingenter (0-1), leading off the seventh.

After a single by Joe Panik and an out, Longoria laced a double to the wall in left field, scoring both baserunners to give San Francisco a one-run lead.

Longoria took third on the Padres' throw to the plate, then scored what turned out to be the difference-making run on a sacrifice fly by Pablo Sandoval.

The Padres got within 6-5 in the eighth on Ian Kinsler's eighth homer of the season, but they never got another baserunner off either Tony Watson or Will Smith, who recorded his 15th save.

Thanks to a two-run homer by Steven Duggar, his fourth, in the fourth inning, the Giants led 3-1 going into the fifth, where right-hander Tyler Beede and reliever Trevor Gott fell victim to a walk and three Padres infield hits.

The second, by Fernando Tatis Jr., scored Wil Myers to get San Diego within 3-2 and set the stage for a two-run hit by Eric Hosmer.

What made Hosmer's single unusual was that it never left the infield. His one-hopper deflected off Gott's arm and in the direction of third baseman Sandoval, whose throw was late to first base, allowing the tying run to score.

Tatis never hesitated rounding third and also raced home to complete the two-run play that put the Padres on top 4-3.

Tatis had earlier hit the game's first pitch off Beede for a home run, his eighth of the season.

Mark Melancon (3-1), who pitched a scoreless seventh inning with two strikeouts, was credited with the win.

Longoria and Panik had two hits apiece for the Giants, who evened their record on an eight-game homestand at 2-2.

Tatis and Hosmer collected two hits and two RBIs apiece for the Padres, who lost for just the third time in eight meetings with their National League West rival this season.

Neither starting pitcher got a decision.

Searching for his first major league win in his sixth career start, Beede was charged with four runs and five hits in 4 2/3 innings. He walked two and struck out a career-best seven.

Padres rookie Chris Paddack allowed three runs and six hits in five innings. He walked one and struck out six.

Paddock recorded his first career hit in the game, one of the Padres' three infield singles in the fifth inning.

The Giants out-hit the Padres 9-7.

--Field Level Media