SAN FRANCISCO – It was the play of the game, the fire extinguisher on the intense desires of a Giants team and fans sensing a miraculous comeback win Sunday night until those hopes were doused by the greatest ballplayer ever to wear a UC Davis Aggies uniform.

As he has all October, Daniel Descalso, the St Louis Cardinals' slight second baseman, elevated his game and his stature in one nerve-wracking moment when a play had to be made and Descalso made it.

On the first night of the National League Championship Series against the Giants, a 6-4 Cardinals win was as tense and tight as advertised.

Postseason baseball comes down to single moments when games are won, reputations are made and fans remember 50 years later the plays paving the way to the World Series.

It's still early, but Descalso is writing a compelling personal narrative in the context of a Cardinals franchise steeped in big wins via big performances by big-game players.

Only five years removed from his days at UCD's Dobbins Stadium, and five days from his 26th birthday, Descalso's moment came early Sunday night.

It was the bottom of the fourth inning when Descalso went full extension – when he reached as far as his 5-foot-10 frame would go – to snare a certain RBI hit struck by Angel Pagan, the Giants' center fielder.

If Pagan's hit bleeds through the Cardinals' infield, as it seemed destined to do as the ball jumped off Pagan's bat, Brandon Crawford surely would have scored the Giants' fifth run of the inning. That would have turned a 6-0 Cardinals lead entering the bottom of the fourth into a 6-5 cliffhanger with Giants runners in scoring position.

"A few breaks here and there," said Giants manager Bruce Bochy afterward.

Who knew what might have happened but for Descalso?

The ball Pagan hit carried the hopes of another miraculous chapter in the Giants' story of 2012. It would have been right in line with the Giants going to Cincinnati last week and winning three games from the Reds to advance when the Reds hadn't lost three consecutive games at home all season.

Then Descalso somehow reached Pagan's hit. He snared it in his glove while hitting the infield dirt with the front of his uniform. He then flung the ball to shortstop Pete Kozma to force Aubrey Huff at second base, snuffing out the Giants' rally.

There was talk in the press box that it was a nice play that would surely be forgotten in the coming onslaught of runs by both teams.

But that was it. A Marco Scutaro single in the fifth inning and a Pagan single just beyond Descalso's reach in the ninth inning were all the Giants could muster after their explosion in the fourth.

It turned out that Descalso's moment was the moment of the game.

Yes, Cardinals sluggers Carlos Beltran and David Freese hit big home runs early as St. Louis took a 6-0 lead.

But once Giants starter Madison Bumgarner was lifted in the top of the fourth, the Cardinals didn't get another hit.

If Pagan gets a hit and Descalso can't reach it …

"Looking back, that was the turning point," Descalso said in the visitors' locker room surrounded by a press corps noticing him more each day. "It was nice to kill that rally."

Descalso looks like a throwback player in his baggy Cardinals uniform. He hit only .227 with four home runs and 26 RBIs in the regular season.

But in the postseason, he's hitting .308 with two huge home runs and six RBIs. Friday, he got the clutch single that tied the score in an eventual 9-7 Cardinals win over the Washington Nationals – a game the Nationals had led 6-0. Sunday, he was 2 for 4 with a double and scored a run.

Raised in the Bay Area as an A's fan, Descalso played three stellar seasons at UC Davis. In the 2007 amateur draft, the Cardinals took him 112th overall – the highest any Aggie has ever gone.

"I still stay in touch with my coaches there," Descalso said. "I still go to practices during the offseason. I absolutely feel connected to Davis."

With many more October nights like this one, they might want to start thinking about immortalizing Descalso at Dobbins Stadium. His legend is growing.

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