MINNEAPOLIS -- The Padres knew what all the sharpies and experts were thinking about this one: Mismatch with a capital M.

Here was Darrell May, winless with a 5.20 ERA, being asked to duel the Twins' 2004 Cy Young Award winner, Johan Santana, on the floor of the Metrodome.

"This was a game, going in, where people were writing us off and didn't give us a chance," Dave Roberts said. "For us to come together and find a way to win shows how good we can be."

With Roberts taking his role as catalyst seriously, with May pitching with remarkable composure under difficult circumstances, and with Damian Jackson showing again why he's someone you want holding a bat with the bases loaded, the Padres frustrated Santana and beat his Twins, 5-1, to take the series in front of 31,371 quiet fans and go 3 1/2 games up on the National League West competition.

"I faced him last year and got shut out, 2-0," May said, referring to one of his 19 losses with the Royals against Santana and the Twins. "It feels good to come back and have a good game like this. I knew it was going to take a good game to beat him."

Pitching for the third time in six days, and coming off a relief effort lasting 5 2/3 innings Wednesday night in Detroit, May knew he was on a short leash and went to the mound determined to "make them put the ball in play early. And the only way to do that is with first-pitch strikes."

Sixty of May's 89 deliveries were strikes, catcher Miguel Ojeda doing for the lefty what Robert Fick had done for Brian Lawrence on Saturday night in the absence of Ramon Hernandez, sidelined by a sprained left wrist.

An inning after Roberts' solo homer on a changeup in the sixth showed Santana (7-3) was human, Jackson delivered the telling blow: a two-out, bases-clearing double between third base and the glove of third baseman Glenn Williams.

Turning on a 93-mph fastball with lightning bat speed, Jackson brought home three Padres who'd coaxed walks off Santana -- Phil Nevin, Brian Giles and Xavier Nady -- and sent the great lefty to the showers blowing off steam at home-plate umpire Kevin Kelley.

"You can't look for a particular pitch," Jackson said. "This isn't the reigning Cy Young guy for nothing. He knows what he's doing. I was looking for a strike, hoping to get the barrel on it and find a hole. That's what happened.

"It was a fastball down and in, and I caught the barrel and got it fair. I tried to turn on it and hit it as hard as I can by third base in that area. It was a drawn-in infield; they do that with me and Dave Roberts, trying to defend against the slow roller."

Jackson is a career .366 hitter with the bases loaded, driving in 38 runs in 41 at-bats -- not that he seems to put too much faith in those or any numbers.

"I just play," he said. "I don't try to pay much attention to past performances. This is a game of adjustments. Baseball players make adjustments every day, every at-bat. You try to get better. Don't be the same guy. If you hit .300, you want to hit .400."

A perfect segue to Tony Gwynn. Jackson spent much of the offseason working out with the Padres' legend, now the coach at San Diego State. Many of Gwynn's lessons find their way into Damian's thought processes on a daily basis.

"I think about trying to keep my head still, taking away as much of my body as I can, using my hands," Jackson said. "Absolutely, I try to think about those things and make adjustments and go from there."

Roberts likewise used his mind and quick hands to pull Santana, a man he'd never faced before Sunday, and get the Padres even after Matthew LeCroy homered leading off the fifth for the Twins.

"With a guy with that stuff," Roberts said of Santana, "you just battle. That's what I did. It was a 2-2 count, and he left a changeup up. For me to get that hit, it gave us some life. The big thing was Darrell matching him pitch-for-pitch. That gave us confidence we're in the ballgame, and anything can happen. Hopefully, we can build on this."

May outdueling Santana was certainly not to be expected. The quiet lefty who came to the Padres from the Royals during the offseason surrendered just two singles and the opposite-field homer by LeCroy.

"What an effort by May on three days' rest," Padres manager Bruce Bochy said. "He was hitting his spots, and had three pitches going. He was very impressive."

The Padres added an insurance run in the eighth against Jesse Crain when Ryan Klesko singled and scored on Giles' double. Rudy Seanez, Akinori Otsuka and Scott Linebrink pitched an inning each in relief of May and combined for five strikeouts, two each by Seanez and Linebrink.

After starting the road trip with four consecutive losses, getting swept in Detroit, the Padres got their offense back in gear in the Metrodome, producing 16 runs and 37 hits in the three games. They've managed to retain their NL West lead despite a 5-12 record in June.

"That was a good win," Linebrink said. "It kind of salvaged the road trip. It would have been tough going back having won only one game."

Amazing what a couple of well-timed Ws will do.