But the reigning World Series champions hadn't performed much better. Entering this series, San Francisco's 17-35 record since May 13 was the Major Leagues' worst.
The Giants have bolstered their confidence at a critical juncture. Instead of stewing in their struggles during the four-game All-Star break, which begins on Monday, they can relax with clear consciences and return mentally as well as physically refreshed.
"It puts us back on course," manager Bruce Bochy said of the series victory. "Hopefully, we'll play this way when we come off the break."
Though the Giants trail the division-leading D-backs by 6 1/2 games, they're positioned for a surge. San Francisco's schedule after the break begins with a nine-game homestand against the D-backs, Reds and Cubs. Should the Giants trim their division deficit by a couple of games, they'll regain some relevance in the race.
Closer Sergio Romo said that during this series, he and his teammates regained the knack for "getting back to that confidence and expecting things to go right. Going on the field expecting to win."
But Romo spoke those words before Sunday's finale, in which the Giants performed as if the intensity and euphoria of Tim Lincecum's no-hitter the previous night had drained them. San Diego scored in each of the first five innings. By contrast, San Francisco mustered one run in six innings off Padres starter Eric Stults (8-7), who entered the game with a 6.23 ERA in three previous starts this season against the Giants.
In the ever-important category of pitching, concern grew in one area for the Giants and eased in another.
Barry Zito was charged with four runs in two-plus innings. He's now 0-6 with a 9.89 ERA in eight road starts, compared with a 4-1 record and 2.45 ERA at AT&T Park. This matched his second-shortest start with the Giants since he joined the club in 2007. It also was his shortest stint since a 1 2/3-inning performance on April 16, 2011, at Arizona.
Overall, Zito has a 1-6 record and 4.86 ERA in his last 15 starts, and opponents are batting a NL-high .313 off him.
Bochy, who typically avoids speaking harshly of underachieving players, remained true to form regarding Zito (4-7).
"He's pitched some big games for us. We haven't forgotten that," Bochy said, clearly indicating that the left-hander will not be removed from the rotation, at least not immediately.
With his remark, Bochy also proved mindful that the Giants won Zito's last 11 starts in 2012, including those in the postseason. Zito also pitched seven-inning shutouts in three of his first four starts this year.
But shutouts were far from anybody's mind after Zito allowed three home runs -- Chris Denorfia's one-out clout in the first inning and back-to-back drives by Nick Hundley and Will Venable in the second. With the All-Star break at hand and rested relievers in the bullpen, Bochy hurriedly pulled his starter.
"My concentration wasn't what it should have been," Zito said. "I threw too many pitches down the middle of the plate. The three home runs were an indication of that. When I'm at my best, I'm [going] pitch to pitch. Sometimes, when I scuffle, I'm getting out of the moment a little bit."
Zito continued to downplay his road woes, stating, "That's really not an issue," though he admitted, "I know what the numbers are saying."
In a more upbeat development, one physically challenged reliever, Santiago Casilla, and a mechanically challenged one, Jeremy Affeldt, provided encouragement by pitching scoreless innings in the sixth and seventh, respectively.
Casilla, making his first appearance since May 20 after undergoing surgery to remove a bone cyst near his right knee, surrendered an innocuous single and threw 13 of his 17 pitches for strikes. He pronounced himself "normal," which is a positive remark coming from a man with a 1.80 ERA.
Raked for three runs in one-third of an inning by the Mets last Tuesday, Affeldt made his second shutout appearance in a row.
"I just fixed my [arm] slot a little bit," Affeldt said. "My breaking ball isn't landing in the on-deck circle now."
And on deck for the Giants are 68 games, most of which they must win to keep the season compelling.