SAN FRANCISCO — Jim Harbaugh’s San Francisco 49ers sure have a knack for leaving tough losses behind.

They’ve never lost two games in a row under the reigning NFL Coach of the Year.

This time, the 49ers had all of four days and no choice but to forget in a hurry; first place in the NFC West was on the line.

Alex Smith threw a 12-yard touchdown pass to Delanie Walker late in the third quarter and San Francisco held off the Seattle Seahawks 13-6 Thursday night to give the 49ers a victory in their long-awaited division opener.

Frank Gore ran for 131 yards and the 49ers (5-2) hung tough on defense late in a game featuring two teams allowing fewer than 16 points per game.

Alex Smith went 14 of 23 for 140 yards in a second straight subpar performance.

Walker’s score was San Francisco’s first touchdown in seven quarters. NFC rushing leader Marshawn Lynch finished with 103 yards for Seattle (4-3).