Colorado (68-93) at Houston (91-70)

The Houston Astros weren’t expecting Roger Clemens to pitch well enough to be a candidate for a seventh Cy Young Award when they lured him out of retirement last winter. They just wanted someone to help lead them back to the playoffs.

The Rocket can improve his Cy Young chances and lead the Astros to the postseason when he pitches on three days’ rest as Houston closes the regular season against the Colorado Rockies at Minute Maid Park.

The Astros won the middle game of the series 9-3 on Saturday, extending their franchise-record home winning streak to 17 and moving one game in front of San Francisco in the wild-card race.

The Giants led Los Angeles 3-0 in the ninth inning Saturday, but the Dodgers rallied for seven runs in their final at-bat, ending San Francisco’s hopes of winning the NL West and putting them behind Houston in the race for the NL’s final playoff spot.

Roy Oswalt pitched the Astros to victory on Saturday, becoming the NL’s first 20-game winner. But while Oswalt struggled to find his form earlier in the season, Clemens carried the Astros.

The 42-year-old Texas native ended his five-year stint with the New York Yankees after the World Series last October. Following a brief retirement, Clemens was convinced to return to his hometown of Houston, along with former Yankee teammate Andy Pettitte, and help pitch the Astros back to the postseason for the first time since 2001.

With an 18-4 record, 2.98 ERA and 218 strikeouts, Clemens has a legitimate chance to add to his record six Cy Youngs by coming up big Sunday—much as he has done nearly every time out during Houston’s playoff drive.

The hard-throwing right-hander is 6-0 over his last 10 starts, with the Astros winning all but one of those outings—a 6-5 loss at Montreal on Aug. 13. On Wednesday, Clemens allowed four runs and five hits over six innings, but did not receive a decision as Houston beat NL Central champion St. Louis 6-4.

Clemens struck out eight, walked one and didn’t take long to let everyone know he’d be back on the hill on short rest if the Astros needed him.

“I’ll be ready to start or do whatever we need me to do,” Clemens said.

Manager Phil Garner didn’t take long to confirm that Clemens would get the ball.

“That could be the biggest game we play all year,” Garner said. “I don’t want to leave any doubt. I think you’ve got to give it your best shot.”

Clemens will be opposed by Colorado right-hander Jamey Wright, who is 0-9 with a 7.64 ERA in 14 career appearances, including 13 starts, against the Astros.

If the Astros lose Sunday, and the Giants beat the Dodgers, Houston will have to travel to San Francisco for a one-game playoff Monday. If the Astros clinch Sunday, they will travel to Atlanta for Game 1 of the NL division series.

“It just shows that you should never give up,” Houston’s Jeff Bagwell said. “The middle of August was a tough situation. We just kept grinding and grinding and here we are.”