Updated

Seattle, WA (SportsNetwork.com) - What a difference two and a half weeks make.

The Seattle Seahawks rode their defense to beat the San Francisco 49ers again as the bitter rivals continue heading in opposite directions.

Marshawn Lynch ran for 91 yards and a touchdown and the Seahawks stifled the 49ers in the second half, eliminating them from playoff contention with a 17-7 victory on Sunday.

Seattle (10-4) allowed 178 yards to San Francisco (7-7) in the first half, but clamped down and limited the 49ers to a meager 67 over the final 30 minutes.

The Seahawks outscored the 49ers 14-0 in the second half.

Seattle outgained San Francisco 379-164 during its 19-3 victory in Santa Clara on Thanksgiving Nov. 27, then racked up 440 yards while limiting the potent offensive attack of first-place Philadelphia to 139 during a 24-14 win last Sunday.

The red-hot Seahawks clash with Arizona in Glendale next Sunday night with first place in the NFC West on the line.

"We're having a great time right now," Seahawks safety Earl Thomas said. "I think we did great overall the whole game."

The Seahawks have won four in a row and seven of their last eight, while San Francisco has dropped three consecutive games, including a 24-13 defeat to woeful Oakland last Sunday.

Russell Wilson was 12-of-24 for 168 yards with a touchdown and an interception, while Jermaine Kearse caught five passes for 78 yards for Seattle, which has beaten San Francisco four straight times at home and recorded its first season sweep in the series since 2007.

Colin Kaepernick completed 11-of-19 passes for 141 yards for the 49ers, who lost running backs Frank Gore (concussion) and Carlos Hyde (ankle) along with linebacker Chris Borland (ankle) to injury.

"I'm aware of it and I understand what it means," 49ers coach Jim Harbaugh said of his team missing the postseason. "We'll never give in, keep fighting."

Sunday was the seventh time in their last eight contests that the 49ers failed to score more than 17 points.

The 49ers held a 7-3 advantage when the Seahawks took over at their own 40 midway through the third quarter.

Lynch picked up 15 yards on a left end run and Wilson hit Paul Richardson for an 11-yard completion to move the chains on a 3rd-and-10 and move the ball to the San Francisco 13-yard line. Lynch's 4-yard TD plunge three plays later capped the 10-play, 60-yard march and staked Seattle to a 10-7 lead late in the third.

The Seahawks defense then forced a three-and-out and found the end zone again, although they were aided by a controversial roughing the passer penalty.

Bryan Walters returned Andy Lee's 53-yard punt 19 yards to the San Francisco 44. Wilson took a zone-read keeper 19 yards to the 49ers' 20, with the penalty coming three snaps later on a 3rd-and-5.

Wilson tossed an incomplete pass to Richardson, but Nick Moody hit Wilson's chest with his helmet and was flagged. Wilson then flipped a quick slant to Richardson two plays later for a 10-yard score.

The 49ers then took the ensuing 7:50 off the clock, but Bruce Miller was stuffed on a 4th-and-1 at the Seattle 38 and they never threatened offensively again.

Seattle opened the scoring late in the first quarter on its second possession. Wilson flipped a 10-yard completion to Doug Baldwin on a 3rd-and-6 to move the ball to the San Francisco 44.

The second of two Eric Reid unnecessary roughness penalties put the Seahawks in field goal range and Steven Hauschka split the uprights from 38 yards out.

San Francisco answered with a touchdown on its ensuing series.

Kaepernick rolled right and floated a 31-yard completion to Garrett Celek down the right sideline. Anquan Boldin hauled in a low throw from Kaepernick on a 3rd-and-11 for a gain of 15 to get the 49ers to the Seattle 40.

Gore was stuffed for no gain on a 3rd-and-1 from the Seattle 10 and Harbaugh elected to go for it on fourth down. Gore then scampered off left tackle for a 10-yard score to cap the 11-play, 85-yard trek and give San Francisco a 7-3 cushion early in the second.

Wilson lofted a perfectly thrown ball to a well-covered Kearse down the right sideline and Kearse was able to corral it for a gain of 47. Seattle was able to get down to the San Francisco 30, but a Justin Britt holding call took it out of field goal range on first down. Dan Skuta sacked Wilson on 3rd-and-17 for a 2-yard loss to put the ball at the 39 and the Seahawks elected to punt.

Seattle drove to the San Francisco 29 on its final touch of the second, but Reid intercepted Wilson on the final play of the half and returned it 73 yards to the Seahawks' 24 before time ran out.

Game Notes

Seattle, which gained 152 rushing yards, had averaged 204.6 yards per game and 5.36 per carry over its last five games coming in ... The Seahawks kept the ball for 28:58 after holding it for at least 35 minutes in their last four ... Seattle was 8-of-14 on third down, while San Francisco was 6-of-15.