JACKSONVILLE, Fla. (AP) -- Maybe the Jacksonville Jaguars took Houston lightly.
The Texans certainly believed so. The scoreboard may have indicated it, too.
Domanick Davis ran for a career-high 150 yards and a touchdown and Houston crippled Jacksonville's postseason chances with a 21-0 victory Sunday.
"I knew we had a good chance coming in here, but for some reason these guys don't respect us and they came out and played like it," Texans defensive tackle Seth Payne said after Houston held the Jaguars to a franchise-low 126 yards..
The Jaguars, coming off a big win at Green Bay, looked nothing like a team with so much to gain.
The offense had some excuses. Running back Fred Taylor missed the game with a sprained left knee, ending his streak of consecutive starts at 46 games, and quarterback Byron Leftwich sustained a mild concussion in the first quarter.
The shutout was the first in team history for Houston and marked the first time the Jaguars have been blanked since a 44-0 drubbing at Detroit on Dec. 17, 1995.
This one could be far more costly than that loss to the Lions in Jacksonville's inaugural season.
Because Baltimore lost at Pittsburgh, the Jaguars (8-7) could have taken control of the final AFC wild-card spot with a victory against Houston (7-8). Instead, they will need to win next week at Oakland and have other teams lose to return to the postseason for the first time since 1999.
"They're sitting there worried about Baltimore and Pittsburgh. They should have been worried a little bit about us," Texans defensive end Gary Walker said.
The Jags have no one to blame but themselves -- because they did little on offense and couldn't stop Davis all afternoon.
"We just didn't show up," Pro Bowl defensive tackle Marcus Stroud said.
Leftwich struggled from the start. He misfired on his first three passes and fumbled early. He picked up the loose ball and then took a shot to the head when sacked by Robaire Smith.
He missed a play before returning on the next series. But he wasn't the same. He overthrew receivers and looked lost in the pocket at times. Coach Jack Del Rio benched him with 4:04 to play, replacing him with David Garrard.
"He told me I looked kind of woozy. I couldn't do anything about it," said Leftwich, who still appeared dazed 30 minutes after the game.
Leftwich finished 6-of-14 for 35 yards with an interception.
"I was hit pretty hard, but I was able to come back," Leftwich said. "I don't know how much it affected me. It's something we're going to have to take a hard look at Monday and see if I was moving around the same."
The Texans, meanwhile, moved the ball with ease. They finished with 333 yards, much of it thanks to Davis. His previous career high was 129 yards, set last season against the New York Jets and tied last month against Tennessee.
Davis also caught five passes for 39 yards.
"You missed one tackle with that guy, and it was like he was out of the gate," Jags linebacker Mike Peterson said.
The Texans scored on the opening possession, a 65-yard drive capped by Davis' 1-yard run. They made it 14-0 in the second after Davis broke loose for a 44-yard gain and then Andre Johnson made a spinning 10-yard catch in the end zone.
They added a defensive score with 3:11 to play. Antwan Peek picked up a fumble and returned it 66 yards for his first career
"This is the best defensive game we've had in our three-year history," coach Dom Capers said. "It shows you the kind of pride and character they have."
The Texans overcame three muffed punt returns -- they recovered two of them and the Jags missed a field-goal attempt following the other -- and two interceptions by David Carr to sweep the series against Jacksonville and finish 4-2 in the AFC South.
"This is a team we've had success against, and for some reason they don't respect us," Payne said. "I hope they keep disrespecting us."
It was 40 degrees at kickoff and 10 degrees cooler with the wind chill. Because of the weather, the stadium was about half full at kickoff and nearly empty in the final minutes. ... Del Rio said he would not have put Leftwich back in the game had he known he had a concussion. ... Davis' 150 yards rushing were the most by one player against the Jags since Chicago's Anthony Thomas had 160 in the 2001 season finale.