WASHINGTON (AP) — Doesn't matter how bad things look for the St. Louis Cardinals. Trailing by a bunch, down to their last strike, they simply stay calm and do what it takes to win.

Erasing an early six-run hole in Game 5 slowly but surely, the defending World Series champion Cardinals got a tying two-out, two-run single from Daniel Descalso and a go-ahead two-run single from Pete Kozma in the ninth inning and came all the way back to beat the Washington Nationals 9-7 Friday night and win their NL division series.

It was the largest comeback ever in a winner-take-all postseason game, according to STATS LLC. No other club in this sort of ultimate pressure situation had come back from more than four down.

First-year manager Mike Matheny and the wild-card Cardinals, the last team to clinch a playoff spot this year, will open the NL championship series at San Francisco on Sunday.

Down 7-5 with two outs in the ninth against Nationals closer Drew Storen, the Cardinals twice were a strike away from losing. But Storen walked both of those batters, Yadier Molina and David Freese, setting the stage for the unheralded Descalso and Kozma — Nationals manager Davey Johnson even called the rookie "Cosmos" before Game 4 — to come through.

When Cardinals closer Jason Motte got Ryan Zimmerman to pop out to second base a half-hour past midnight, the Cardinals streamed from the visiting dugout for a rather muted celebration, all in all.

This was nothing new to them.

Over the past two years, St. Louis is 6-0 when facing elimination, including victories in Games 6 and 7 of the 2011 World Series against Texas.

Down to their last strike in the Fall Classic a year ago, trailing by the exact same 7-5 score, the Cardinals rallied in Game 6 and then took the championship in what turned out to be the final year with the club for slugging first baseman Albert Pujols and then-manager Tony La Russa. Now Matheny, who got the Cardinals into the playoffs as the second NL wild-card team on the next-to-last day of the regular season, has them back in the NLCS.

And to think: Washington, which won the NL East and led the majors with 98 wins, got off to as good a start as possible Friday.

Seven pitches, three runs. Just like that, Jayson Werth's double, Bryce Harper's triple and Zimmerman's homer got the hosts jump-started in their first Game 5.

That opening outburst, plus a big third inning highlighted by the 19-year-old Harper's homer, made it 6-0.

St. Louis was not about to go gently into the night, though. The Cardinals chipped away, chipped away. One run off 21-game winner Gio Gonzalez in the fourth, a pair in the fifth, another in the seventh off Edwin Jackson — the Game 3 starter and loser, and an all-around surprising choice for midgame relief.

Suddenly, it was 6-4. Descalso's homer made it 6-5 in the eighth. And a four-run ninth completed the reversal.

In Game 6 of last year's World Series, the Cardinals twice were one strike from losing, before Freese's two-run triple in the ninth, then Lance Berkman's tying RBI single in the 10th. Freese's homer won it in the 11th, and St. Louis went on to a 6-2 victory in Game 7.

Here they were, doing it again.

All in front of a Nationals Park-record crowd of 45,966 witnessing the first postseason series in the nation's capital in 79 years. So seemingly close to a significant triumph, the Nationals — and their fans — left disappointed.

The Nationals went down without All-Star ace Stephen Strasburg. The team said he'd thrown enough this year and didn't put him on the playoff roster.