Alex Smith passed for two touchdowns and the San Francisco 49ers’ defense dominated the visiting Arizona Cardinals on Sunday en route to their eighth straight victory 23-7.

Frank Gore battled through knee and ankle injuries to rush for 88 yards and Michael Crabtree finished with 120 receiving yards as the 49ers (9-1) maintained their five-game lead on the Seahawks in the NFC West.

San Francisco can clinch its first division title since 2002 with a victory at Baltimore on Thursday, coupled with a Seattle loss to Washington on Sunday.

San Francisco’s defense, which leads the NFL at 14.5 points allowed per game, limited the Cardinals to 229 yards and 11 first downs, including 52 and two in the first half, and also enjoyed a 44:16-15:44 time of possession advantage.

The 49ers’ offense, though, hardly resembled a playoff-bound unit in the first half. They had two field goals blocked and missed another, and their three trips into the red zone resulted in six points as they managed only a 9-0 lead.

San Francisco put the game away with a 13-play, 84-yard drive in 7:48 to start the second half, capped by Smith’s 8-yard touchdown pass to Kyle Williams to make it 16-0.

Smith’s 18-yard scoring toss to Vernon Davis later in the third quarter put the 49ers ahead 23-0.

John Skelton, who had won two straight games in place of the injured Kevin Kolb, was 6 of 19 for 99 yards with three interceptions, and Beanie Wells had 33 yards rushing for Arizona (3-7).

Richard Bartel replaced Skelton and threw his first career touchdown pass – a 23-yarder to Larry Fitzgerald – in the fourth quarter.