Never mind that they almost let this one slip away with a poor second half.

Steve Slaton scored two touchdowns and the Texans built a big lead before holding on for a 24-21 win over the San Francisco 49ers on Sunday.

The Texans (4-3) led 21-0 at halftime, then withstood a rally led by backup quarterback Alex Smith. Eugene Wilson's interception on fourth down halted the 49ers' last-gasp drive.

"We get down, they get up and they all of a sudden grabbed the momentum of the game," Texans coach Gary Kubiak said. "But we made some big plays late and defensively Eugene made a big play so it was a big, big win."

San Francisco (3-3) benched Shaun Hill after a terrible first half, and Smith threw three touchdowns to Vernon Davis to close the gap.

"I just thought it was time to make the switch," 49ers coach Mike Singletary said. "It was as simple as that. No long, drawn-out thought process. But let's make the change."

Singletary wouldn't say who would start next week.

Former Texas Tech star Michael Crabtree started in his NFL debut and had five receptions for 56 yards.