Tramaine Brock perfectly read Matt Schaub's first pass of the night, jumped in front for an interception and ran 18 yards for a touchdown just 90 seconds into the game, setting the tone for a stellar defensive performance in a 34-3 victory over the Houston Texans on Sunday night.
Things only got better for Brock and San Francisco, and worse for Houston's beleaguered quarterback. Schaub threw three interceptions in all before being replaced in the fourth.
Colin Kaepernick tossed a 64-yard touchdown pass to Vernon Davis and Frank Gore ran for 81 yards and a score in his second straight impressive prime-time game. The 49ers (3-2) are right back in the NFC West race with Seattle after the Seahawks (4-1) lost at Indianapolis. Each team has beaten the Texans (2-3) and lost to the Colts, and Seattle still must visit San Francisco on Dec. 8.
Anthony Dixon added a 2-yard touchdown run for the NFC champions, while Brock had a second interception and nearly a third.
Kaepernick went 6 for 15 with 113 yards as the 49ers won their second straight in emphatic fashion following the first two-game losing streak under third-year coach Jim Harbaugh. Kaepernick completed four of his first six passes, then threw seven straight incompletions before connecting with Bruce Miller early in the fourth quarter and then Davis' TD.
After being outscored 56-10 in the back-to-back losses against Seattle and Indianapolis, the 49ers have overwhelmed their opponents 69-14 over the last two games.
Brock's ball-hawking defense was a big reason in this one.
He ran his initial interception back 18 yards for his first career pick six, then gained 13 yards on his second pick midway through the second quarter. That set up Dixon's second TD of the year.
Brock nearly had a third late in the first half but was called for defensive pass interference, and rookie safety Eric Reid dropped a would-be interception right at him late in the third.
Even fringe defensive lineman Tony Jerod-Eddie - an injury replacement for Ray McDonald - got in on the interception fun in the third quarter.
Schaub's nightmare, monthlong stretch continued when he threw his first pass of the game for a pick-6, giving the beleaguered Texans quarterback an interception returned for a TD in four straight games.
On the next drive, Randy Bullock hooked a 45-yard field goal try wide left - and the 49ers capitalized afterward again with Gore's touchdown late in the first quarter.
Bullock produced the Texans' lone points with a 41-yard field goal in the third.
Missing three key defenders for the second straight game, San Francisco's opportunistic D didn't flinch and kept the penalties in check after early season problems with flags.
All-Pro linebacker Patrick Willis sat out a second straight game with a groin injury that also kept him out at St. Louis on Sept. 26, and the Niners also missed linebacker Aldon Smith again as he undergoes treatment for substance abuse. Cornerback Nnamdi Asomugha is still nursing a knee injury.
Gore followed up his 153-yard performance in a 35-11 road rout of the Rams with another solid night.
Schaub wound up 19 of 35 for 173 yards and a sack in the Texans' third straight loss, which came on the heels of a 23-20 overtime loss at home to San Francisco archrival Seattle last week. Houston has its first three-game skid since the end of 2011. Fans in Texas were already furious and burning his jersey - and there's a sign over one freeway calling for Schaub's ouster. This certainly won't help matters as supporters call for backup T.J. Yates.
In a stadium set to be imploded after the season, Schaub himself imploded. He could be seen muttering to himself with a shell-shocked expression walking off the field as coach Gary Kubiak buried his face in his hands.
Kubiak turned to Yates in the fourth quarter and Ben Tate lost a fumble on Yates' second play, with San Francisco's Tarell Brown recovering.
The 49ers, who had lost their last two Sunday night games both to the Seahawks, amassed 177 yards rushing with five different players each making a run of 11 or more yards.
San Francisco's 21-point halftime lead matched its biggest under Harbaugh.
Texans tight end Owen Daniels made six receptions for 60 yards, giving him at least one catch in 88 straight regular-season games.