SAN DIEGO -- The D-backs knew coming into this pivotal four-game series with the Padres that the opener was going to be the hardest one to win.

The Padres had ace Jake Peavy going, and the right-hander has always been tough against them. Monday was another example, as Peavy struck out 11 as San Diego registered a come-from-behind 3-1 win in front of 25,763 at PETCO Park.

The loss trimmed Arizona's lead in the National League West to two games, but didn't dampen the D-backs' confidence, especially with ace Brandon Webb set to take the mound in Game 2 on Tuesday night.

"We feel good," outfielder Eric Byrnes said. "We knew this was going to be our toughest one to win, [so] you know it's not a big deal. Coming into it and facing Peavy, we're facing their [ace] tonight, and they have to face ours tomorrow, so we feel real good about Webby going, and as long as he goes out there and pitches the way he's been pitching, I think we'll be fine."

Webb will be hard-pressed to match the performance of Peavy, who fanned 11 D-backs, including seven straight at one point, over seven innings. Peavy racking up strikeouts against Arizona hitters is nothing new. In four starts against the D-backs this year, he's got 45 punchouts and fanned nine straight during the April 25 game in Phoenix.

The lone mistake Peavy made in the game was a hanging slider in the sixth that Byrnes drove over the left-field wall for the game's first run.

"That's literally the only [pitch to hit that] I saw all night," Byrnes said.

The D-backs' strategy against Peavy (15-5) was to try to run up his pitch count and force him to leave the game. Peavy, though, was able to make it through seven before turning a lead over to Heath Bell in the eighth and Trevor Hoffman in the ninth.

Arizona starter Livan Hernandez was on top of his game, as he mixed his pitches and frustrated San Diego's batters throughout.

"Livan's good," Peavy said. "Livan's pitched in big games down the stretch for his whole career for a lot of years. I knew it was going to be a tough night. Livan throws the ball a little off the plate and gets you to swing at it and gets the call and did tonight. He's tough to beat."

It looked like the Padres might finally get on the scoreboard in the sixth, when Peavy and Brian Giles led off the inning with singles. A sacrifice by Mike Cameron put runners at second and third with the heart of the order coming up.

Hernandez (9-9) managed to strike out Milton Bradley on a 61 mph curveball before Adrian Gonzalez flied out to left to end the threat.

"To get out of the inning with three, four up there, Bradley and Gonzalez, you really feel like that's a momentum shift," Arizona manager Bob Melvin said.

That seemed to be the case as Hernandez easily retired the first two San Diego hitters in the seventh, but then he walked Josh Bard. It was Hernandez's first walk of the evening and it would prove to be his undoing.

Geoff Blum followed Bard to plate and with a 1-2 count on him, Hernandez threw back-to-back breaking balls that Blum refused to chase.

"I didn't want to walk the guy," Hernandez said of Blum. "I threw two breaking balls down and he wasn't swinging. I wanted to come for something for a strike because I walked the guy before him. I felt very good with the fastball."

Hernandez wanted to throw a fastball on the outside corner, but the pitch caught just a little too much of the plate. Blum was able to pull it into the right-field seats for a 2-1 San Diego lead.

"It's tough [Hernandez's curveball], you see it for a while; it has a good bite to it," Blum said. "You have to fight your instincts and stay back. He threw a fastball, which kind of shocked me."

The Padres added an insurance run in the eighth on a homer by Bradley, and despite putting two runners on against Hoffman in the ninth, the D-backs were not able to get them home.

"We kept battling," Melvin said. "With Jake on the mound you try to grind away and find a way to beat him, but we've got our guy going tomorrow. Tip you hat to both teams. They played with a lot of energy and at a high level. It was a good game, we just came up on the wrong side of it."