The Padres hit into four double plays and were 1-for-11 with runners in scoring position, stranding 10 on base against seven Giants pitchers.
"Both teams had their chances. There was some clutch pitching that drove this game and not-so-timely hitting. Someone is going to get a hit and it happened to be Maxwell at the end," said Padres manager Bud Black.
The Padres managed seven hits -- the Giants had only six -- and struck out seven times, giving them 39 in four games this season, the most in the big leagues.
San Diego second baseman Jedd Gyorko grounded into double plays in his first two at-bats against Tim Hudson, who walked five in five innings, but managed to escape any real trouble.
"Myself alone, I had a couple of really good opportunities to give us the lead," said Gyorko, who was 1-for-5. "In situations like that [runners on base], you want to get something to elevate."
The Padres got a runner to third base with one out in the seventh inning, but Yangervis Solarte hit into a 1-6-3 double play. Gyorko's lone hit in the ninth inning got a runner to third base with two outs, but Clint Barmes grounded out to end the inning.