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.
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.
"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.
Mario Williams had two sacks as he stayed in Manning's face most of the day. Manning was 25-of-34 for 247 yards with two touchdowns and one interception.
Williams still seemed to be in shock after the game.
"I've never seen anything in my life like that," he said of the fourth quarter. "For that to happen, I can't even remember seeing anything like that growing up. It's just devastating."
Slaton brought Houston within 10-7 on a 1-yard run early in the second quarter set up when Jackson was called for pass interference on Johnson in the end zone. Slaton's other score came on a 1-yard run early in the fourth quarter that pushed the lead to 27-10.
Houston settled for a 37-yard field goal by Kris Brown to tie it at 10 in the second period after Ahman Green tripped and fell on a direct snap. Green, playing for the first time since Week 1, had 12 carries for 47 yards.
Brown added a 43-yard field goal in the third quarter.
Joseph Addai scored on a 1-yard run that gave Indianapolis a 10-0 lead. That drive was kept alive when Manning found Wayne for a 36-yard gain on fourth-and-1.
Wayne finished with seven receptions for 97 yards and Dallas Clark had five receptions for 81 yards.
The Colts were relieved to get a win to leave the Texans in last place in the AFC South. Wayne described how much better a 2-2 record feels compared to being 1-3.
"Last place and not last place," he said. "You never want to lose, period. Whenever it goes against you, you kind of look at it. We lose this game, we're in last place."
Johnson surpassed 5,000 yards receiving for his career with Sunday's performance. ... The win ties Manning with Terry Bradshaw for seventh on the NFL's all-time list with 107. ... Williams has four sacks this season.