SAN DIEGO » The San Diego Chargers have regained their December swagger, thanks to Vincent Jackson’s return and a smash-mouth defense.

Jackson caught a career-high three touchdown passes, Philip Rivers surpassed 4,000 yards passing for the third straight season and the Chargers beat Alex Smith and the San Francisco 49ers 34-7 last night to stay alive in the AFC West race.

Jackson reminded the Chargers just what they missed when he sat out 10 games during a nasty contract dispute.

"It’s like I had never left," said Jackson, who had his first three TD grabs of the season, of 58, 11 and 21 yards.

"He seems to be in midseason form," Rivers said. "I feel like he’s been here for 15 weeks. That’s a credit to the way he practices."

The Chargers (8-6) pulled within a half-game of AFC West leader Kansas City (8-5), which lost 31-0 at San Diego on Sunday.

San Francisco was probably the toughest test left for the Chargers, who finish with games at Cincinnati (2-11) and Denver (3-10). If San Diego wins out and the Chiefs lose once, the Chargers will win their fifth straight division title.

The Chargers came within 4:26 of having consecutive shutouts for the first time in their 51-year history.

The 49ers (5-9) could wind up 7-9 and in a three-way tie and still win the NFC West, the NFL’s weakest division.

Rivers and Jackson came out early in the fourth quarter and the Chargers leading 31-0.

Rivers was 19 of 25 for 273 yards, giving him 4,141 for the season. He tied Hall of Famer Dan Fouts’ team record set from 1979-81. Jackson had five catches for 112 yards.

"He and Phil have such a good rapport," center Nick Hardwick said. "They both know what’s going on, and they’ve studied for hours together. We were expecting him to come in and explode, and that’s what he’s done. He’s a beast. He does things other players can’t do, and he did it tonight."

Unhappy that the Chargers didn’t give him a long-term deal, Jackson sat out the first seven games. He then missed three more games while serving a team-imposed suspension. The move cost him some $3 million in salary.

When he returned at Indianapolis on Nov. 28, he pulled a calf muscle two plays in and was done for the night and the next game.

On the fourth play from scrimmage, Rivers wound up and threw deep. The 6-foot-5 Jackson slowed down and reached out over 6-foot Nate Clements’ head to make the catch at about the 15 before outracing the cornerback into the end zone.

First Quarter
SD–Jackson 58 pass from Rivers (Kaeding kick), 12:53.

Second Quarter
SD–FG Kaeding 25, 6:03.
SD–Jackson 11 pass from Rivers (Kaeding kick), 1:19.

Third Quarter
SD–Tolbert 1 run (Kaeding kick), 4:52.

Fourth Quarter
SD–Jackson 21 pass from Rivers (Kaeding kick), 12:06.
SD–FG Kaeding 39, 7:38.
SF–Westbrook 3 run (Reed kick), 4:26.

A–67,820.

RUSHING–San Francisco, Dixon 6-33, Westbrook 8-22, A.Smith 1-6. San Diego, Mathews 17-56, Tolbert 17-46, Hester 2-7, Sproles 2-1, Volek 3-(minus 2).

PASSING–San Francisco, A.Smith 19-29-1-165. San Diego, Rivers 19-25-0-273.

RECEIVING–San Francisco, Morgan 7-106, Crabtree 3-17, Walker 3-14, Ginn Jr. 2-14, Westbrook 2-8, V.Davis 1-4, Dixon 1-2. San Diego, Jackson 5-112, McMichael 5-55, Sproles 5-30, Washington 2-49, Sperry 1-35, Hester 1-(minus 8).

MISSED FIELD GOALS–None.

NFL STANDINGS

AMERICAN FOOTBALL CONFERENCE

NATIONAL FOOTBALL CONFERENCE

x-clinched playoff spot

WEEK 15

Yesterday
San Diego 34, San Francisco 7

Sunday
Kansas City at St. Louis, 8 a.m.
Washington at Dallas, 8 a.m..
Houston at Tennessee, 8 a.m.
Arizona at Carolina, 8 a.m.
Philadelphia at N.Y. Giants, 8 a.m.
Detroit at Tampa Bay, 8 a.m.
Cleveland at Cincinnati, 8 a.m.
Buffalo at Miami, 8 a.m.
Jacksonville at Indianapolis, 8 a.m.
New Orleans at Baltimore, 8 a.m.
Atlanta at Seattle, 11:05 a.m.
Denver at Oakland, 11:15 a.m.
N.Y. Jets at Pittsburgh, 11:15 a.m.
Green Bay at New England, 3:20 p.m.

Monday
Chicago at Minnesota, 3:30 p.m.