For the Houston Astros, it was another day, another superb pitching performance, another hero from nowhere. For the Los Angeles Dodgers, it was another wasted day, another wasted pitching performance, another shocked, frustrated clubhouse scene.

Today's Houston hero was Denny Walling, 27, a .234 hitter during the season, an irregular who takes out his pent-up energy on a punching bag after games, most of which he spends on the bench.

This afternoon, Walling came on in the 11th inning and used his energy to hit a two-out, bases-loaded line drive over Dodger right fielder Derrel Thomas' head, giving the Astros their second dramatic victory in 20 hours, this one 1-0 over the flailing Angelenos.

The victory gives the Astros a 2-0 lead in the National League West Division playoff series, meaning they need to win just one of three games this weekend in Dodger Stadium to take a second straight division championship.

"I like our chances," said second baseman Phil Garner, who scored the game's only run. "But this thing is still one hell of a rat race."

A rat race perhaps, but a classic one. For the second consecutive game, these teams engaged in a splendid dogfight that centered on brilliant pitching, outstanding fielding and minimal clutch hitting.

The Dodgers came away from Tuesday's 3-1 opening loss seemingly unaffected, even though they lost on a dramatic ninth-inning home run by journeyman catcher Alan Ashby. They rationalized the situation by pointing out that Nolan Ryan had simply overpowered them with a two-hitter and by noting that a split was all they wanted in Houston anyway.

Today, however, they had countless chances to earn that split, leaving 12 men on base during the 11 innings, three times failing to score a man from third with less than two out. "That's what really kills you," said Dusty Baker, one of the Dodger stars who failed to come through. "To have all those chances and not come through once. To get two great pitching performances and only score one run in two games."

Both teams had chances to break the tie during the first 10 innings. The Astros got eight scrambling innings from knuckle-baller Joe Niekro before Dave Smith came on to pitch two innings in relief.

Dodger starter Jerry Reuss was even better than Niekro, retiring the first 13 batters and giving up just five hits during his nine innings. Steve Howe kept the game scoreless in the 10th. But the entire series was embodied in the 11th. During those 25 minutes, 11 men batted, four pitched and two managers tried to outmaneuver each other while the drained fans began to think the game might continue indefinitely.

It started with Astros Manager Bill Virdon bringing in top reliever Joe Sambito.

Sambito had been up and down in the bullpen since the sixth inning. "I had no rhythm the first three batters," he said. "I was overthrowing and they were teeing off."

Sambito got one out when Tony Scott ran down Pedro Guerrero's drive 400 feet from home plate at the center field fence. But then pinch hitter Steve Yeager lined a double off the left field wall. "He crushed it," Sambito said. "Anywhere else, it's out. But fortunately this isn't anywhere else."

Playing a hunch, Dodger Manager Tom Lasorda sent 36-year-old Reggie Smith to hit for Howe. Smith has been hurt all season and hit just .200 in 35 at bats. "But he's been in these situations before," Lasorda said. "I thought he might lose one."

Instead, Smith just lost, striking out on four pitches for the second out. The next scheduled batter was second baseman Davey Lopes, the only Dodger with two hits in the game.

But Lopes didn't get to hit. Lasorda called him back from the on-deck circle and sent up Mike Marshall, 21, who has just 25 major league at bats.

"Davey hurt his hand sliding in the seventh inning," Lasorda said. "He told me he couldn't swing the bat. Why Marshall? Because I thought he was the best guy."

Marshall had no more luck than Smith. Sambito had his fast ball under control and he struck out the rookie on four pitches.

Lasorda went to Dave Stewart -- the pitcher who had given up Ashby's game-winning home run Tuesday -- apparently following the theory that you should get right back on the horse after falling off.

Garner greeted Stewart with a solid single up the middle and then took off on Stewart's first pitch to Scott. "I told Tony if I got on I would be stealing on the first pitch," Garner said. "I was really surprised he didn't lay off the ball."

Scott had failed to bunt Garner to second in a similar situation in the ninth, so Virdon had given him the hit sign. He used it to crack a Stewart fast ball to right center, sending Garner to third. It also sent Stewart to the dugout, and Lasorda turned to Terry Forster.

Forster got Jose Cruz to pop to short left field. Lasorda brought on right-hander Tom Niedenfuer to face the right-handed hitters. He also ordered Niedenfuer to intentionally walk Cesar Cedeno to get to the much slower Art Howe, hoping for a double play.

Instead, Niedenfuer struck out Howe on three pitches. Virdon then turned to Walling, sending him up for Dickie Thon, even though Thon had two hits.

With two out, the Dodger dugout relaxed a bit. Coach Danny Ozark, who had been frantically positioning the outfielders with none out and one out, sat down. That left Thomas on his own.

"I was surprised to look up and see how shallow Thomas was playing," Walling said. "We had been talking about how shallow they normally play in the dugout. But with two out, I thought he would go back and play deeper."

Walling got a 1-1 fast ball just where he wanted it and hit a line drive to Thomas' right. The former infielder got a good jump on the ball but his desperate reach was not enough, and the ball bounced past him for the winning hit.