KANSAS CITY, Mo. (AP) -- The injuries kept mounting for the Houston Texans, and yet they still had the ball with a chance to take the lead on the unbeaten Chiefs in the fourth quarter Sunday.
That's when the stingy Kansas City defense truly shined.
Case Keenum was forced into an incompletion on first down, and then stripped by linebacker Tamba Hali on second down.
Derrick Johnson hopped on the loose ball with 1:34 remaining in the game, allowing Kansas City to run off the rest of the clock and preserve a 17-16 victory.
"When they can pin their ears back, they're very, very difficult," Texans coach Gary Kubiak said. "They came and got us pretty good there late in the game. I'm proud of my team's effort, but I'm just very disappointed in the result."
The result was another frustrating loss for the banged-up Texans (2-5), who are riding their first five-game skid since Nov. 6-Dec. 11, 2005.
They were already without quarterback Matt Schaub, who missed the game with right ankle and foot injuries.
But they were dealt two more crushing blows when running back Arian Foster left with a hamstring injury in the first quarter, and linebacker Brian Cushing had to be taken up the tunnel on a cart with an injury to his left knee in the second half.
Foster said that he hoped to be back soon, but Kubiak said the injury to Cushing could be serious. "It doesn't look good," he said.
Nothing is looking bad these days for the Chiefs (7-0), who trail only the 2003 team for the best start in franchise history.
In the Super Bowl era, 31 previous teams started 7-0 and all of them made the playoffs. Fifteen went on to play in the Super Bowl and nine won it.
"It was a physical game, the kind of a game this team needs to go far," said Jamaal Charles who ran for 86 yards and a touchdown. "I'm glad we came across this team."
Alex Smith also had a touchdown run for the Chiefs.
"We've got a great group of guys, honestly. Hungry guys," the quarterback said. "They appreciate being around each other, and it's fun. It's fun coming to work every day."
Things haven't been much fun for the Texans lately.
Even when things went well, such as a nice drive to start the game that ended in a field goal, there was a reason to grimace -- in this case, Foster heading to the locker room and emerging from it in a gray sweatsuit.
The Chiefs answered with an 82-yard drive that Charles capped with a short TD plunge, but the Texans pulled back ahead when Keenum hit DeAndre Hopkins on a 29-yard touchdown reception.
Keenum finished with 271 yards passing in his first NFL start.
"It's a big stage against a really good football team," Keenum said. "I learned that it's one or two plays here and there that make a difference."
The Texans still led 10-7 when they pinned Kansas City at its 3-yard line midway through the second quarter. Smith proceeded to guide the Chiefs 97 yards in 15 plays -- he was 8 of 8 for 75 yards on the drive -- and used all but 56 seconds on the clock to regain the lead.
Smith scored on a 5-yard draw when he froze the defense on a fake handoff to nobody.
Bullock tacked on two more field goals for Houston, and Ryan Succop hit one for the Chiefs, who came within inches of extending their 17-16 lead early in the fourth quarter.
Tight end Anthony Fasano caught a pass at the goal line and was ruled down, and Chiefs coach Andy Reid challenged the spot to no avail -- he thought it was a touchdown. Charles was stuffed on the next play, and Smith's pass to wide open Sean McGrath on fourth down was out of bounds.
It turned out that it didn't matter. The Chiefs' defense made sure of that.
"Our team played really hard there toward the end," Keenum said. "We put the offense in position and me in position to go down and win the game, and we didn't. I didn't make plays there at the end. You have to give credit to Kansas City."
NOTES: The Chiefs had five sacks, giving them 36 on the season. ... Ben Tate had 50 yards rushing for Houston. ... The Texans did not commit a turnover until Keenum was stripped at the end. They had an AFC-leading 15 turnovers coming into the game. ... Smith had 231 yards passing.