Someone had to win the NL Central.
Brad Ausmus hit a three-run homer in a six-run seventh inning as the Astros clinched.
"We've been second place the last three years, so now we get to find out what the other side feels like," said Mike Hampton (15-10), who pitched a four-hitter. "You think you are dreaming, but it's our time to tell everyone else to take a seat."
Houston, only 82-77, stumbled to the division title by going 23-28 since Aug. 1. Second-place Pittsburgh, which dropped four games back going into its season-ending three-game series in the Astrodome, was even worse, losing 18 of its last 29 games.
But the Astros didn't care how they got into the playoffs.
"This team has so much heart," left fielder Luis Gonzalez said. "We finally have a chance to relax and enjoy it. The next three days are going to be fun around here."
Jeff Bagwell and Craig Biggio, the Astros' best players, embraced as the game ended and a championship banner was unfurled in center field.
"We've been through so much together, getting so close so many times and now to finally get where we want to be is very exciting," Bagwell said.
"They blasted us when we didn't make any trades before the deadline and said the Astros didn't want to win," General Manager Gerry Hunsicker said. "But we're one of the teams going on in the playoffs."
The Astros last clinched a title on Sept. 25, 1986, when Mike Scott pitched a no-hitter against San Francisco.
"For all the years I've been here as player, broadcaster and manager, I've seen a lot of memorable games, and this is one of the most memorable," said Manager Larry Dierker, a former Astro pitcher and broadcaster. "This is a credit to all the hard work these guys have done. They've come so close before. I'm happy for them. They deserve this."
Bagwell hit the Astrodome roof with a popup in the sixth inning, what is believed to be the first fair ball to strike the top since the stadium opened in 1964. The ball appeared to be headed toward third, but pitcher Jeremi Gonzalez (11-9) caught it for an out.
McGwire hit a fly ball to medium left in the first and struck out swinging in the third and sixth. He singled in the eighth off Brett Tomko, and again in the 10th against Stan Belinda.
He came up with the winning run on second and two outs in the 12th, but struck out swinging against Scott Sullivan.
McGwire is tied with Seattle's Ken Griffey Jr. for the major league home run lead, and both need six homers to tie Roger Maris' 36-year-old single-season record of 61.
Both McGwire and Griffey have three games remaining.
Catching Maris will be a longshot--McGwire will need to average two homers a game. But precedent suggests it's possible.
Twice in his career, both times with Oakland, McGwire has hit five homers over a two-game span. He hit three against Cleveland on June 27, 1987, and two against the Indians the next day. In 1995, he hit two against Boston on June 10, then three the next day, also against the Red Sox.
Atlanta, which beat the Phillies for the 10th time in 12 games this season, improved to a major-league best 100-59. The Braves won 104 games in 1993 and also achieved the feat twice in Boston, winning 102 in 1892 and 1898.
Tom Glavine, who'll start the second game of the division series, gave up one run and six hits in seven innings, struck out seven and walked one.
Montreal 3, Florida 2--Expo pitcher Pedro Martinez became the 14th pitcher since 1900 and the second this year to record 300 strikeouts in a season at Montreal.
Martinez struck out nine to increase his franchise record to 305. He gave up one run in seven innings, lowering his major league-leading ERA to 1.90.
Martinez, in his final start of the season, reached 300 strikeouts when Kurt Abbott failed to check his swing on a 3-and-2 pitch leading off the fourth inning. Philadelphia's Curt Schilling got his 300th on Sept. 16.
Martinez is seeking to become the first pitcher since Steve Carlton in 1972 to finish a season with 300 strikeouts and an ERA under 2.00. Carlton struck out 310 and had a 1.98 ERA while going 27-10 in 1972.
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BESTS OF THE DAY
Player Team Performance Team's Result Brad Ausmus Houston Three-run home run Win Todd Zeile Dodgers 2 home runs Win Darren Lewis Dodgers Three-run home run Win
Player Team Performance Team's Result Mike Hampton Houston 9 innings, 4 hits, 6 strikeouts Win Tom Glavine Atlanta 7 innings, 1 run, 6 hits, 7 strikeouts Win Pedro Martinez Montreal 7 innings, 1 run, 9 strikeouts Win