SAN FRANCISCO — Shaun Hill and the San Francisco 49ers' beleaguered offense clicked for just one quarter. Still, those 15 minutes were more than enough time to bury the miserable St. Louis Rams.

Hill threw two touchdown passes and Frank Gore rushed for another score during San Francisco's 28-point second quarter, and the 49ers snapped their six-game losing streak with interim coach Mike Singletary's first victory, 35-16 over the Rams today.

Vernon Davis and Bryant Johnson caught TD passes from Hill, who went 15-of-20 for 213 yards and ran for a second-quarter score in San Francisco's first win since Sept. 21 against Detroit, when the 49ers were above .500 with a different coach and starting quarterback.

Singletary had lost twice, including last Monday's tough defeat in Arizona, since taking over for Mike Nolan and replacing J.T. O'Sullivan with Hill, who coolly improved to 3-0 as a starter at Candlestick Park.

Gore rushed for 106 yards and two touchdowns, making several gritty runs in the second quarter as the Niners (3-7) took advantage of Marc Bulger's three turnovers to match the highest-scoring period in franchise history while leaping to a 35-3 halftime lead.

San Francisco had six previous 28-point quarters since the merger, but the club had scored four offensive touchdowns in a quarter just once, when Joe Montana threw four TD passes in the fourth quarter at Philadelphia in December 1989.

Hill, a career backup making his fourth career start, is no extraordinary Joe, but he had a perfect passer rating at halftime — and he merely had to be solid while Bulger's fumble and two ghastly interceptions doomed the Rams (2-8), who have dropped four straight.

Bulger went 34-of-53 for 295 yards for the Rams, who trailed by 32 at halftime just one week after falling behind 40-0 midway through a 44-point loss to the New York Jets. Donnie Avery had a career-best nine catches for 93 yards, but a blowout loss to the struggling 49ers might be even more humiliating than that historic defeat at the Jets' hands.

A swath of injuries compounded the insult, with left tackle Orlando Pace, right guard Richie Incognito and cornerback Ron Bartell all getting sidelined in the first half. St. Louis also played without injured running back Steven Jackson for the third time in four games.

Isaac Bruce holds most of the Rams' career receiving records after 14 seasons with the club beginning in Los Angeles, but he had just one catch for 20 yards in his first game against St. Louis with the 49ers. Mike Martz, the longtime Rams coach, decidedly outfoxed St. Louis interim coach Jim Haslett in Martz's first meeting with the Rams as division rivals.

After Davis caught a short TD pass early in the second, San Francisco's next three touchdowns all were set up by Bulger. Gore carried on four straight plays for a score after Bulger's fumble on a snap, and Hill threw himself over the goal line for a 1-yard TD run about 4› minutes later.

Johnson capped the rally with a 2-yard TD catch 34 seconds before halftime on a well-placed fade from Hill, who had a 158.3 passer rating at halftime, going 12-of-14 for 192 yards. San Francisco had 201 yards and 11 first downs in the second quarter alone.

The 49ers went back to their usual selves in the second half, getting shut out and even committing three consecutive false starts to begin the fourth, giving them four total penalties in the first 6 seconds of the period.

Dane Looker caught a TD pass for St. Louis with 1:56 to play.