Was It a Swing of Momentum?

On the wall in left-center field at Houston’s Minute Maid Park is a large banner proclaiming “Back-To-Back Wild Card Champions.”

Forty-four years in the league, eight previous trips to the playoffs and that’s what the Astros choose to brag about?

Not on Monday night. Not with a three-games-to-one lead over the St. Louis Cardinals in the best-of-seven National League championship series, a 4-2 lead in the ninth inning of Game 5 and two strikes on the Cardinals’ David Eckstein.

Surely that banner was about to be covered with another one that read “2005 National League Champions.” It would be the Astros’ first.

But, as the baseball world knows, the Astros’ celebration was delayed, and perhaps denied, when Albert Pujols hit a towering three-run homer to give the Cardinals a 5-4 victory and send the series back to St. Louis for Game 6 tonight and, if necessary, Game 7 Thursday.

As depressing a sight as it was for the Astros to watch Pujols’ blast, even more frightening home-run images have to lurk in the back of their minds. Such as:

* Dave Henderson’s ninth-inning home run in Game 5 of the 1986 American League championship series, which broke the backs of the Angels, who went on to squander a three-games-to-one lead.

* David Ortiz’ 12th-inning home run in Game 4 of last year’s ALCS to start the New York Yankees, leading three games to none, on the downward spiral to the greatest collapse in baseball history. New York didn’t win another game.

* Kirk Gibson’s home run for the Dodgers in Game 1 of the 1988 World Series against the Oakland A’s. While the Dodgers still had to win three more games, some felt that set a tone that the A’s were unable to reverse.

The Astros don’t have to look elsewhere to know that a game-breaking home run can turn into a back-breaking moment. They need only look back to a year ago when they were also in the NLCS, they were also facing the Cardinals and they also enjoyed a 3-2 lead heading into Game 6 in St. Louis.

On that night, Jim Edmonds hit a 12th-inning walk-off home run to force a Game 7 and St. Louis went on to win that one as well.

Seasons are decided on momentum, and nothing powers momentum like the force of a baseball sailing into the stands with the game on the line.

Houston General Manager Tim Purpura, however, isn’t buying that theory. Not in this case.

“We carry on,” he said upon arriving in St. Louis on Tuesday. “That’s what we’re doing, we’re carrying on. We don’t say, ‘Oh, woe is us, the season is over.’ We get on a plane, we come here and we’re ready to go. It was a great mood on the plane today, a real positive mood. And I think that says a lot about our players.... There’s nobody giving up, nobody is hanging their head, Nobody is saying, ‘Oh, we were this close to the World Series.’ Everything I heard from the guys today was, ‘We’ve got to get ‘em [today].’ ”

St. Louis Manager Tony La Russa has to be excused for enjoying the view of a momentous home run from the winners’ dugout.

He was the Oakland manager the night Gibson hit his shot.

“This side is a lot better,” he said.

As for tonight, La Russa said, “the simplest and healthiest frame of mind for our club to have is that we are good enough to win the next game that we play. Otherwise, why should we play it?”

La Russa tried to downplay any lingering effects of Pujols’ home run.

“If we were playing [Tuesday],” La Russa said, “and it was a quick turnaround, maybe there would be a little carry-over from Houston. But they have an off day and they are going to collect themselves. Our guys might still be celebrating and might not be ready to play.”

Not much chance of that. As any student of the game could tell him.