SAN DIEGO (AP) _ As far as the San Diego Padres are concerned, it all comes down to Trevor Hoffman.

Al Martin, who had three RBIs on Sunday, knows it. So does Kevin Walker, who got his first big league win. And Hoffman certainly knows his comfort zone.

The closer earned his 11th save in a 4-3 win over the Montreal Expos. It was his second save in the series and his fourth in six games. Earlier this month, when the Padres struggled, Hoffman went a week in between appearances.

``I can't put a price tag on what it's like to be able to be out there and help the club and be in my situation,'' Hoffman said.

His situation, of course, is the ninth inning, with the game on the line.

Martin, San Diego's left fielder, has the best view of Hoffman warming up in the bullpen.

``It's almost like a security blanket knowing that if you can get to the eighth with the lead that you're going to see Hoffy down there throwing balls over the mound before he gets on the mound,'' Martin said, describing how Hoffman plays long toss before settling in with warmup pitches.

Walker (1-0) pitched a scoreless sixth, which was made livelier by third baseman Phil Nevin's two errors.

``When you've got Hoffman coming in the ninth, I felt real good about getting'' the win.''

San Diego's bullpen has gotten the decision in the last four wins and five of the last six.

The Padres swept the Expos and extended their winning streak to four, their longest since July. The Expos lost their fifth straight.

Martin drove in San Diego's first three runs, and the go-ahead run scored when Expos third baseman Andy Tracy dropped a popup.

Martin, who had been 2-for-32 with runners in scoring position this year, hit an RBI double in the first and a two-run single in the fifth. He added a triple in the seventh to finish 3-for-4.

Although manager Bruce Bochy moved Martin from the leadoff spot to the No. 2 hole in mid-May, he called Martin into his office and expressed confidence in him.

``That really helps out, because you can start doubting yourself,'' Martin said.

After Martin tied the game at 3 in the fifth by poking a two-out, two-run single over the glove of second baseman Jose Vidro, the Padres scored the winning run without benefit of a hit in the sixth. They got a walk, a fielder's choice, a hit batsman and two errors.

Bret Boone reached when his grounder erased Ryan Klesko at second for the second out. He then stole second, with an errant throw by catcher Brian Schneider allowing him to take third. After Ruben Rivera was hit by a pitch from Carl Pavano (5-2), Wiki Gonzalez hit a popup that Tracy dropped after Boone had already crossed the plate.

``I just missed it,'' Tracy said. ``It hit me right in the bottom of the glove and it popped out.''

Martin started the Padres' comeback with a first-inning double to score Eric Owens, who hit a leadoff single and stole second.

Lee Stevens' two-run homer, his 11th, highlighted the Expos' three-run first off Stan Spencer, who finished with nine strikeouts in five innings.

Notes: With starter Woody Williams on the disabled list and Sterling Hitchcock likely headed there, the Padres are set for another round of callups. RHP Adam Eaton, currently with Double-A Mobile, is scheduled to make his major league debut on Tuesday and Rodrigo Lopez is to be called up for the second time this season from Triple-A Las Vegas to start Wednesday in Hitchcock's spot. ... Hitchcock plans to seek a second opinion on the sprained ulnar collateral ligament in his throwing elbow from Anaheim Angels Dr. Lewis Yocum.