The little bitty Astros won again, 1-0 in 11 innings, the second straight time they have taken the big boy Philadelphia Phillies in overtime, and now Houston is one victory away from bringing the World Series in from the cold.

Here in the eternally room-temperature Astrodome, Joe Morgan's leadoff triple in the 11th and Joe Niekro's 10 innings of six-hit pitching may have made it possible for Bowie Kuhn to leave his winter longjohns at home for a while.

The Astros went up, two games to one, in this best-of-five series for the National League championship when Morgan rattled the right field fence with a line drive hit so hard it carried 390 feet before Bake McBride, a sprinter, could move the 50 feet necessary to flag it down.

It was hit so hard that Morgan dared to think big.

The biggest little man was thinking very big when he saw McBride crash into the fence, missing the catch "by three inches maybe four," McBride would say. As the ball bounced back toward the infield, Morgan thought he might turn the line drive into an inside the park home run.

All that's left of Joe Morgan, though, is the mongoose-quick swing and the courage to think big. He has a bum knee, hurt a week ago. He can't run. Even as McBride sagged against the fence, dazed, Morgan barely was around first. He dragged his unwilling left leg with him in pursuit of a victory that might help put the Astros into World Series for the first time in their 19 year existence.

"My leg wasn't hurting today," Morgan said, fibbing, "and when I saw the ball bounce away from McBride, my leg really wasn't hurting. I was thinking of running on home, because if you get a chance to score, you have to do it. When I got 15 feet from third base, the coach pointed at the base. So that ended that."

Desperate now, desperate with baseball's best left handed relief pitcher in trouble, desperate with Tug McGraw having given up that leadoff triple to a 37-year-old lame warrior -- desperately, the Phillies walked the next two men intentionally to load the bases with no one out.

Rafael Landestoy was sent in to run for Morgan at third, because Manager Bill Virdon knew full well it was time to get a whole body out there. And when Denny Walling lifted a McGraw fast ball into a medium depth fly to left field, the ball game was Landestoy's to win.

"I knew, with Landestoy's speed, he would try to score," said the Phillies' left fielder, Greg Luzinski, a mediocre thrower. "I had to go back three or four steps for the catch, and I just did all I could with the throw."

Landestoy easily outran the throw and skidded across the plate, smiling in the duststorm, before the ball hit the catcher's glove.

The Astros had cause for some gloom, however, because they lost their good center fielder, Cesar Cedeno, for the remainder of postseason play. Cedeno caught his foot on first base grounding into a double play in the sixth inning and suffered a compound dislocation of his right ankle. There also was ligament damage and he was carried off the field on a stretcher to a hospital and operated on.

For Saturday's fourth game, the Astros will have their 24-game winner on the mound, Steve Carlton, going against Houston's Vern Ruhle, who last week was able to complete only two innings against the Dodgers before reopening a cut on the index finger of his throwing hand. Ruhle is said to be well healed now.

"We've got the best pitcher in the world ready to pitch for us," said Pete Rose, the Phillies' first baseman and designated jawboner. "And after he wins, we just have to win one more."

The master of the confounding knuckleball, Niekro allowed only one Philly as far as third base today. He allowed two runners in an inning only twice. He retired 16 of 17 men from the fourth through the ninth inning.

Philadelphia's only real threats to score were in the third and ninth thrown out at home -- when he shouldn't have been running -- on a simple bouncer to third baseman Enos Cabell. Perhaps Rose's foolishness was the result of frustration, for these Phillies not only left 10 men on base in the last four innings of game two, they left men at second in the first two innings today.

With two outs in the ninth, Niekro hit batter Garry Maddox, who promptly stole second base. Larry Bowa was walked intentionally to bring up Bob Boone, who lashed a line drive toward left center "that I thought was in there."

But the Astros' left fielder, Jose Cruz, playing shaded toward the gap out there, caught up to it.

Two more Phillies reached base in the 11th against relief pitcher Dave Smith. Maddox doubled with two out. Again Bowa was walked. Left-handed hitter Del Unser, up for Boone, then struck out.

Next came Morgan. In the eighth inning, he had a chance to drive in a big run. The Phillies were changing pitchers, getting McGraw in to face Morgan with a man on second and one out.

"How about a pop-up?" hollered Rose, Morgan's old teammate on the mighty Reds of yesteryear.

"Nope," Morgan called out from the on-deck circle to his buddy at the base path. "I want a line drive, and I hope they don't catch it."

It was a line drive, hit solidly 330 feet. But it was caught in the gap by the center fielder after a long run and a desperate lunge. Big Joe Morgan, all of 5 feet 7 and 160 pounds, stopped at first base, there by Rose, and threw his arms up in frustration.

Three innings later, on his next time at bat, Morgan limped into third base and as he dragged his bum leg off the field, with 44,443 fans sending waves of applause down on him, the biggest little man raised his helmet in celebration.