ESPN NFL

DENVER -- Fall behind by 20. Mount a furious comeback. Lose by six.

The ugly interceptions didn't play into Peyton Manning's second straight defeat, but so much of the rest of it sounded like a broken record -- the likes of which the Broncos quarterback doesn't want to hear anymore.

Matt Schaub lost a small chunk of his ear after a brutal hit, but still outplayed Manning, throwing for four touchdowns against a confused Broncos defense Sunday to stake the Houston Texans to a big lead on the way to a 31-25 victory.

"We have to learn from this game, address it, be honest, everybody needs to be accountable and try to improve forward," Manning said. "It's not the ideal situation. Everybody would love to be 3-0. That's not the way it is right now."

It is for Houston, which won its first three games for the first time in the franchise's 11-season history and beat Manning for only the third time in 19 tries -- and for the first time ever in a road game.

Manning finished 26 for 52 for 330 yards with no interceptions and two touchdowns. This was his 64th career 300-yard passing game, breaking a tie for the record with Dan Marino. But both of Manning's touchdown passes and 120 of his yards came after the Broncos (1-2) had fallen behind by 20, the way they did in Atlanta last Monday when their rally came up short in a 27-21 loss.

"It's hard to think about anything, really, besides losing two games in a row in a tough fashion," Manning said.

In the Atlanta game, the Denver defense couldn't get the ball back for Manning at the end. This time, it did, but the drive started at the Denver 14-yard line with 20 seconds left and ended with a lost fumble after Broncos receivers tried lateraling at midfield on the last play.

Manning threw three interceptions in the first quarter of the Atlanta game to match his worst quarter in 15 years in the NFL. This time, it was the defense's mistakes, not his own, that put him in the hole.

"Second week in a row we lost by six points," Denver coach John Fox said. "It's the second week in a row we started very slowly. Different side of the ball this time."

Schaub threw for 290 yards. He took advantage of blown coverages to connect with Andre Johnson for a 60-yard score and Kevin Walter for a 52-yard touchdown en route to a 21-5 lead in the second quarter.

After the second score, starting cornerback Tracy Porter was not seen on the field again.

Porter, who returned an interception for a touchdown in Denver's only win this year -- the season opener against Pittsburgh -- spent the rest of the game guarding the Gatorade table on the sideline. Fox said he had a knee injury. Porter's clothes were still hanging in his locker when reporters were asked to leave the locker room.

"We knew that we had to try to get the ball downfield because they had a lot of people committed to the run," said Texans coach Gary Kubiak, the longtime Denver quarterback and assistant coach, who got his 50th career win. "We did what we had to do to win, convinced them that we had to make some big plays and they did."

Schaub's final touchdown was a 14-yard pass to tight end Owen Daniels, who was locked in one-on-one coverage against a slower defender, linebacker Von Miller. It gave the Texans a 31-11 lead with 1:33 left in the third quarter -- placing the Houston defense in the prevent and Manning into desperation mode.

That touchdown pass came about 10 minutes after Schaub was leveled by Joe Mays, which resulted in Denver's second consecutive roughing-the-passer penalty and, eventually, a Texans field goal for a 24-11 lead. Schaub came out for a play and had a big, bloody mark on his left ear.

"I felt fine," Schaub said. "I just lost a piece of my ear. I was bleeding and my helmet came off. So, I had to come out for a play, but I was fine."

Manning had his ups and downs -- making some throws to prove the arm strength is certainly there, but also coming up short on a couple of those 18-yard out patterns that are as routine for NFL quarterbacks as making the bed.

His best downfield throw was the 38-yard touchdown to Brandon Stokley that pulled the Broncos within 31-18 with 9:49 left. His second score was a 6-yard touchdown that ricocheted into Joel Dreessen's hands with 3 minutes left.

There were no interceptions, but that's not to say Houston didn't have its way with the 36-year-old quarterback, who came into the game with 42 career touchdowns against the team he started beating when it was in its expansion season, back in 2002.

Manning's biggest headache in this one was second-year defensive end J.J. Watt, who finished with 2 1/2 sacks and forced a holding call in the third quarter that nullified a 36-yard gain.

"I don't see those numbers of defensive linemen as much. You are looking downfield," Manning said. "I'm probably the wrong guy to ask how he played."

Arian Foster finished with 105 yards on 25 carries for Houston. The Texans converted on four third downs and went 97 yards to take a 14-5 lead when Schaub hit Foster, being covered by defensive lineman Kevin Vickerson, for a 3-yard score that Foster celebrated by blowing kisses to the crowd.

Game notes

DE Elvis Dumervil got his first sack of the season on Denver's first defensive play, a 6-yard loss for the Broncos first safety since 2007. ... In addition to his 2 1/2 sacks, Watt hit Manning in the backfield three times. ... Former Broncos WR Rod Smith was inducted into the Denver Ring of Fame at halftime.