HOUSTON - Headed for another early-season loss, Peyton Manning and the Indianapolis Colts staged a stunning comeback thanks to a colossal collapse by the Houston Texans.

Manning’s late-game poise — and the lack of it for Houston quarterback Sage Rosenfels — helped the Colts scored 21 points in a late span of 2:10. Two touchdowns came thanks to fumbles by Rosenfels, then Indianapolis intercepted Rosenfels’ last-ditch comeback attempt for a 31-27 win Sunday.

Manning threw two touchdown passes, connecting with Reggie Wayne on a 5-yarder with 1:54 remaining for the decisive points. Linebacker Gary Brackett returned a fumble by Rosenfels 68 yards for a score in between Manning’s TD throws.

“All of our team played great football today, played winning football and I made those mistakes that cost football games,” Rosenfels said. “There is no reason we should have lost that game.”

But they did, in incredible fashion.

“I thought we had that passion at the end,” said Colts coach Tony Dungy. “But it was missing during the middle of the game and we’ve got to get that back somewhere.”

Rookie Tom Santi caught the other late score, a 7-yarder to bring the Colts (2-2) within 27-17 with 4:04 to go. It was his first NFL touchdown.

Backup Rosenfels, playing for the ill Matt Schaub, had the winless Texans (0-4) ahead by 17 points before losing two fumbles and throwing an interception. Texans fans had wanted to see Schaub replaced all season, and Rosenfels was nearly flawless for three quarters. Then came one of the worst meltdowns in the history of the young franchise.

Special feature NFL's top shots A look at the best photos from Week 5, including a face-off in Philly. NBCSports.com

After Manning found Santi for his touchdown, Indianapolis attempted an onside kick, but Houston recovered. On the next drive, Rosenfels ran right at defensive back Marlin Jackson, who upended him and knocked the ball loose. Brackett ran it in to make it 27-24.

“For one play I made a really stupid mistake and that started the downward spiral,” Rosenfels said. “I feel like I let those guys down.”

Said Brackett: “I told those guys, ’There’s a lot of time left. Somebody’s got to make a play.’ It just happened to be myself.”

On the ensuing drive, Robert Mathis sacked Rosenfels and stripped the ball at the Houston 19. Manning hit a leaping Wayne in the corner of the end zone, the play was reviewed, and the call was upheld.

Houston got back the ball with almost 2 minutes remaining, but Rosenfels was intercepted by Melvin Bullitt.

The five-time AFC South champion Colts were off to their worst start since starting the 1998 season 0-4 when Manning was a rookie. Manning was looking for his team to get back on track with this game.

Slideshow   The Week in Sports Pictures The Giants on top of the football world, getting ready for the London Olympics and more. more photos

“The encouraging thing is we feel like we can find a little more consistency, we’re capable of scoring more points and we have the players to do it,” he said. “The idea today was to get a little swagger back ... I was proud of the guys for never giving up and fighting ’til the end.”

The Texans played the 100th game in franchise history in their hurricane-damaged stadium with the retractable roof open; the roof couldn’t be repaired in time for Sunday’s game.

Rosenfels’ miscues ruined good days by rookie Steve Slaton and Andre Johnson. Slaton ran for 93 yards and two touchdowns and Johnson bounced back from two poor games with nine catches for 131 yards. Johnson, who had 67 yards in the last two games combined, scored his first touchdown of the season on a 5-yard reception just before halftime for a 17-10 lead.