MONTREAL, SEPT. 17 -- So maybe no one figured a starting rotation built around Dennis Martinez and Pascual Perez would keep a team in a pennant race with the St. Louis Cardinals and New York Mets.

But for the Montreal Expos, help has come from the oddest places and did so again tonight as Perez pitched a four-hitter and Hubie Brooks drove in three runs to beat the Mets, 4-1, before 24,806 at Olympic Stadium.

The victory moved the amazing Expos (82-62) to within 3 1/2 games of the first-place Cardinals and to within 1 1/2 of the second-place Mets. Their odds are still long. They play eight of their last 11 games on the road, including five at Shea Stadium and Busch Stadium.

But from the first day of spring training, when they were putting together a team without Andre Dawson, the Expos had been penciled in for last in the National League East. Now, they have the tape player turned up loud in their clubhouse as they talk of winning it all.

"I really like our chances," Brooks said. "We know we have to keep playing well because the other two teams aren't going to fold. But this was a big one tonight. When we came in here today, we knew we had to win. You hear that a lot, but it was true for us."

He pointed across the clubhouse, toward Perez.

"That man is going to get us over the hump," he said. "That man is going to be the difference."

If that man does, it will be one of the game's greatest reclamation stories. Before winning his last four starts, he was best known for getting lost on his way to the Atlanta ballpark, missing assorted team planes and buses and firing imaginary six-shooters from the mound.

When baseball last left Pascual Perez, he had been released by the Atlanta Braves and was back in the Dominican Republic, "with my parents telling me I was probably through pitching."

At the age of 30, he got a chance from the Expos, who were so desperate for pitching they were signing any and all comers. In Perez, they were hoping to accomplish what they'd accomplished with Martinez, the former Baltimore Oriole, a year earlier.

From nowhere, they've become the bedrock of the Expos' starting rotation. Martinez has gone 9-3, Perez 4-0, but remarkably, Montreal is 22-3 in games started by Martinez (16-3) or Perez (6-0).

Tonight, Perez permitted a first-inning run, then allowed only two more Mets to get as far as second. He walked one, struck out eight and allowed only one base runner the last five innings.

"He was totally in command," Mets Manager Davey Johnson said. "I've never seen him that good. He was even getting his change-up over. He used to be wild, and I'm sure he was wild in a lot of ways. That's about as good as you can pitch."

Perez took the compliments in stride, saying, "I felt strong, and I've felt strong since I came back up. I'm feeling confident. We needed this game. I couldn't sleep before it. I wanted to win it for my teammates."

The Expos, who got three hits apiece from Brooks and first baseman Andres Galarraga, were in a 1-1 tie until the sixth, when Brooks hit his 12th homer of the season.

Mets starter David Cone (5-4) was decent, allowing five hits and three earned runs in six innings. The Mets' bullpen allowed the fourth run in the eighth.

Actually, Perez almost didn't get out of the first inning. With one out, Howard Johnson walked and Keith Hernandez singled to center. Darryl Strawberry singled to drive in Johnson, but Perez got Kevin McReynolds on a forceout grounder and Gary Carter on a liner back to the mound.

The Expos tied it in the bottom of the first when Mitch Webster was hit with a pitch and scored from first on a Brooks double. Like Perez, Cone was lucky to get out having allowed only one run. He followed Brooks' double by walking Tim Wallach, but got Galarraga on an infield grounder and Tom Foley on a pop fly to leave Brooks at third.

Cone got through the next four innings, but, in the sixth, he gave Webster a leadoff walk, then grooved a first-pitch fastball to Brooks, who sliced it over the right field wall for a 3-1 lead.

"I made only two mistakes and both were to Hubie," Cone said. "I thought I pitched pretty well, but when you're in a pennant race, you've got to do better than three runs in six innings."

After Cone got Wallach on a fly ball to left, Galarraga singled. Foley then struck out, but Mike Fitzgerald walked. Cone got out of the inning by getting Casey Candaele on a ground ball to Hernandez at first.

The lead stayed at 3-1 until the eighth. With Doug Sisk pitching, Brooks beat out an infield single and Wallach walked. Galarraga hit a broken-bat chopper to the left of the mound and beat it out for a single to load the bases.

Manager Johnson brought in left-hander Jesse Orosco, who got Vance Law on a fly to shallow center for the first out. Orosco hit Fitzgerald with a pitch to score Brooks before getting Reid Nichols to hit into a double-play grounder to end the inning with the lead at 4-1.

"I'm healthy for the first time all year," Brooks said, "and I want to make a difference in this race. I like our chances right now.

"When you've got a buzz saw on the mound, you're going to score some runs."