Buster Posey's grand slam punctuated a six- run fifth inning, helping the San Francisco Giants claim a piece of history in a 6-4 decision over the Cincinnati Reds in the fifth and deciding game of a National League Division Series from Great American Ball Park.
Brandon Crawford picked up two hits, an RBI and a run scored for the Giants, the World Series winners of two seasons ago who became just the second National League club to win a first-round, best-of-five series after dropping the first two games.
Los Angeles initially accomplished the feat against Houston en route to a championship during the strike-shortened 1981 season.
Pablo Sandoval hit safely twice and scored, while Angel Pagan also drove in a run for San Francisco, which also became the first NL squad since the advent of the wild card era to win a division series after losing two in a row at home to start.
Matt Cain (1-1) lasted 5 2/3 innings, allowing six hits and three runs, while walking two and fanning five. Sergio Romo posted his first career postseason save by recording the final four outs.
"It was huge, coming back from 0-2," Cain remarked. "Winning three games in this ballpark is not something that's easy to do, especially in this situation."
The NL West champions now await the winner of Washington-St. Louis in the other NLDS matchup to compete for the pennant in a best-of-seven series.
Ryan Ludwick homered and drove in two runs, with Brandon Phillips adding two hits and two RBI for the Reds, who have not won a postseason set since the 1995 NLDS against the Dodgers.
"Everyone in this clubhouse did a tremendous job this year," Ludwick said. "It's sad to see it end, but it is and we're all going to move on."
Mat Latos (0-1) departed after 4 1/3 innings and was rocked for seven hits and six runs -- five earned -- with four strikeouts and one walk.
Cincinnati, the NL Central champions, have little to show after a 97-win campaign, their most since going 102-60 in 1976 -- a year that ended with the second of back-to-back World Series titles.
Unlike Game 3 of that season's NLCS, when the Reds rallied with three runs in the bottom of the ninth to stun Philadelphia and head to the Fall Classic, there were no heroics in the Reds' final turn at the plate on Thursday. It came close, however.
Romo walked Zack Cozart with one out then allowed back-to-back singles to Joey Votto and Ludwick -- the latter plating Cozart -- which pulled the Reds within 6-4.
Jay Bruce flied out to center after a 12-pitch at-bat, and Scott Rolen swung at a third strike to end the game.
The visitors broke through with a monster fifth frame. Gregor Blanco led off with a single and came in when Crawford dumped a ball into the right-field corner for a triple. Two batters later, Cozart bobbled a Pagan grounder and Crawford scored for a 2-0 game.
Marco Scutaro walked and Sandoval's line single to left loaded the bases, then Posey forced Latos' exit from the game with a blast that landed in the left- field seats. Sam LeCure set down the next two batters to keep it 6-0 for the Giants.
Cincinnati awoke in the home half on a one-out, two-run double by Phillips, but Cain settled down and retired the final two hitters.
Ludwick began the home sixth with a shot to left, then Bruce walked and Rolen singled. The rally was squashed when Bruce was cut down trying to steal third on the third strike to Ryan Hanigan, and George Kontos retired Drew Stubbs on a groundout.
The Reds also put two on with two outs in the seventh, but Ludwick grounded back to the mound to end the threat.
Three Giants relievers combined to keep the hosts from cutting into their deficit in the eighth. Pagan ended the frame by making a diving grab off a sinking Dioner Navarro liner with two aboard.
San Francisco put two on with one out in the top of the first, but Latos worked out of the jam. He retired 10 in a row from Sandoval's single through Hunter Pence's two-out hit in the fourth.
Cain stranded two in the bottom of the first, and encountered little trouble through the fourth.
San Francisco set a new club playoff record with its fifth straight road victory, eclipsing the original mark of four reached in 2002 ... The Giants head to their sixth NLCS in club history (1971, 1987, 1989, 2002, 2010) ... There have been four American League teams to overcome a similar hole and win the best-of-five division series (1995 Mariners, 1999/2003 Red Sox, 2001 Yankees), but none of those teams had to win all three games on the road ... Cincinnati fell to 3-3 all-time in winner-take-all playoff games, while San Francisco improved to 8-17.