Roger Clemens and Andy Pettitte are always mentioned in that order. You never hear about Pythias and Damon, do you?

Legendary friends are supposed to stay in their proper mythological sequence. But let's give Pettitte his due. He's the man most responsible for radically altering the landscape of both major leagues. Why? Just because he wanted to go home.

The four words that may end up defining the entire 2004 season are, "Lefty, this changes everything." That's what Clemens told Pettitte when he heard that his buddy had dumped the Yankees and mortified George Steinbrenner last December in favor of a much cheaper free agent contract so he could play in Houston where he grew up and lives.

A month and a day later, Clemens, who'd retired to be home with his family in Houston, unretired to become an Astro, too.

"We got Andy, then he brought another pitcher with him, too," cracked Manager Jimy Williams last night. So far, the pair has not done too badly. Everyone expected success, but the ex-Yanks have a combined 11-1 record that has carried the Astros to a 24-17 record, the best mark in the National League.

On Friday, just two days after attending the funeral of R.D. Crumley, a man he thought of as a father figure, Pettitte battled through five determined innings, left with a 4-2 lead, but ended with a no-decision of an eventual 7-4 loss to the Cincinnati Reds. Yet, in a way, Pettitte's ability to allow just one earned run, and hand a lead over to his bullpen on a night where he had a heavy heart, a tired body and his worst stuff was an illustration of why his arrival in Houston is so important. Clemens, 41, will probably be retired again soon. It is Pettitte, 31, who will set the example -- as Clemens has set it for him -- of how to be a tough-minded professional, a poised winner.

"What he's been through both physically and personally this week took its toll," Williams said.

Yet Pettitte would accept no excuses. Criticizing his own high pitch count as "unacceptable" and blaming himself for "putting too much heat on our bullpen," rather than mentioning it was the bullpen that had, in fact, blown his win.

"I felt like coming home to Houston was the right thing for me to do. I think things happen for a reason," said Pettitte. "Maybe one reason was so that I could be with my friend [Crumley] as he was dying from lung cancer. He was 65. He took me hunting ever since I was 15. The last two months, I've been able to stop by his house every morning."

That would have been hard to do from Yankee Stadium. The bond between Pettitte and Clemens is so strong that Clemens also went to Crumley's funeral. "I feel like Roger has been a big brother to me. He's always looked out for me. I think he likes me," said Pettitte, who is so modest that he might be the last to know that he's one of Clemens's favorite people.

The Rocket gets the bigger headlines, as he should, with 317 wins and a 7-0 record with a 1.72 ERA this year. But it is the quiet, smooth-walking, slow-talking Pettitte who perfectly complements Clemens's emotional fire and intimidating fastballs. The combination of their personalities and styles has the potential to transform the Astros if they will pay attention. Clemens epitomizes the best of athletic arrogance, yet he befriends as humble a star in Pettitte as could be found. Both are relentless conditioners of their body and competitors on the field. In a word, they're serious. Soon the Astros may be, too.

Seldom has a team been so dumbstruck by its unexpected good fortune. "I didn't think it was going to happen," Craig Biggio said of signing Pettitte. "The Red Sox were doing so many things last winter I couldn't believe that George would let Andy get away. I didn't think they'd allow him to walk.

"But he took less money to be here. That shows you that to him it was more important to be home. That was his time [to cash in]. . . . A 20-game winner, left-handed, six trips to the World Series," said Biggio. But Pettitte took $31.5 million for three years with much of it deferred until '08 rather than a guaranteed five-year contract for more than $50 million in New York.

"As soon as Andy signed, everywhere in Houston all you heard was, 'What's Roger going to do,' " said Biggio. Perhaps no player has ever been begged so much to keep playing. Pettitte was at the head of the list of cajolers. But Biggio took a unique approach that may have played a role. He asked Clemens to come back not for the sake of his own chances at a ring or any of the Astros players but to "come back for the sake of the whole city."

When Pettitte and Clemens were introduced in the offseason, both Biggio and Jeff Bagwell, who've played 30 seasons combined in Houston without going past the first round of the playoffs, came to the ballpark event like kids waiting for presents to be unwrapped on Christmas morning. "It was like being a fan for a day for Bags and me," said Biggio, who sat in the infield during the ceremony.

If work ethic and preparation play any part, then Pettitte and Clemens should set an ideal example. "Now that they get to hit in the National League, Andy and Roger didn't miss a single batting or bunting practice that we had in spring training at 8:15 a.m.," says Williams. The result? Clemens already has four hits and four RBI, tied for the most of any pitcher. Pettitte, who ripped a single on Friday, takes his batting so seriously that he actually injured himself (and missed three weeks with a strained elbow) in his first game as an Astro while trying to check his swing.

All the Astros are as excited these days as a pitcher who finally gets a chance to hit. Nobody tries to hide his exuberance. "Let's make some memories together," says Clemens.

"Do people actually realize what they're getting to see?" said Williams of Pettitte in his prime and Clemens in a hometown victory lap. "Enjoy this. It's not going to last forever."

Just long enough, perhaps, to make some October memories.