49ers at Seahawks -- Week 16

Where: CenturyLink Field, Seattle, (FieldTurf)

Forecast: High of 44, Low of 39. Overcast, chilly with rain.  

When: Sunday, 8:20 p.m. ET (NBC)

Spread: 49ers by 1

Records: 49ers (10-3-1; NFC West 2-1-1); Seahawks (9-5; NFC West 1-3)

Past results: Two most recent meetings – Oct. 18, 2012: 49ers 13, Seattle 6; Dec. 24, 2011: 49ers 19, Seattle 17. Series record: 49ers lead 14-13.

What matters: The 49ers can lock up the NFC West title with a win and take an important step toward a first-round bye in the playoffs. With two games left, San Francisco holds a half-game lead over Green Bay for the No. 2 seed. Assuming the Packers beat Tennessee and Minnesota over the next two weeks, they would vault past San Francisco if the 49ers were to lose to Seattle or Arizona. A loss would also keep the door open for the Seahawks’ chances at winning the division. If San Francisco loses its next two and Seattle wins out, the Seahawks would be the division champions.

Who matters: DE Ricky Jean Francois. With DE Justin Smith out of practice all week due to an elbow injury, it appears the All-Pro veteran won’t play against Seattle. So, in steps Francois. He was an adequate fill in against the Patriots in the second half when Smith left with the injury, but is a clear step down. The most noticeable difference was the lack of pressure from LB Aldon Smith once Justin Smith was out. Aldon needs three sacks in the last two games to tie Michael Strahan’s NFL single-season record (22.5).

Key matchups:  Jim Harbaugh vs. Pete Carroll. The deal here is that Harbaugh has a 5-1 record against Carroll head-to-head as coaches, dating to their time in the former Pac-10 when Carroll was at USC and Harbaugh at Stanford. Harbaugh orchestrated a win in their first matchup when Stanford was a 41-point underdog and he's 3-0 against Carroll since taking over in San Francisco before last year. This week, both confirmed they have not been exchanging Christmas cards.

LBs Patrick Willis and Navorro Bowman vs. Seattle RB Marshawn Lynch. San Francisco defensive coordinator Vic Fangio spoke highly of Lynch: “He’s definitely, the last two years, the toughest back we’ve gone against and our guys have a lot of respect for him.” Lynch has gone over 100 yards the last two times against San Francisco and ranks No. 2 in the NFL with 1,379 yards rushing. With Justin Smith likely out, there’s even more pressure on Willis and Bowman to keep Lynch contained.

Injuries of note: Justin Smith’s elbow injury is the most noteworthy. He was listed as questionable, along with LB Tavares Gooden (ribs), LB Clark Haggans (shoulder), WR Mario Manningham (shoulder) and DT Will Tukuafu (concussion). Listed as probable: K David Akers (pelvis), G Alex Boone (knee), LB Bowman (shoulder), LB Ahmad Brooks (shoulder), CB Tarell Brown (shoulder), S Dashon Goldson (foot), RB Frank Gore (wrist), G Mike Iupati (shoulder), RB Bruce Miller (shoulder), CB Carlos Rogers (knee), LB Aldon Smith (shoulder), S C.J. Spillman (illness) and LB Willis (shoulder).

Connections: Seattle WR Doug Baldwin and CB Richard Sherman played for Harbaugh at Stanford. Seattle LB coach Ken Norton Jr. and DB coach Kris Richard played for the 49ers. 49ers third-string QB Scott Tolzien preceded Russell Wilson at Wisconsin. S Dashon Goldson played at the University of Washington in Seattle.

Inside stuff: Seattle has a six-game home winning streak dating to last season’s loss to San Francisco, and the 49ers have won their last six primetime games.

Stat you should know: The 49ers allow 4.6 yards per play -- the best mark in the NFL.

Looking ahead: San Francisco wraps up the regular season next week at home against Arizona.

Prediction: 49ers 24, Seattle 19

Follow 49ers reporter Kyle Bonagura on Twitter @CBS49ers and @KyleBonagura.