Where: Edward Jones Dome, St. Louis (FieldTurf, indoors)
When: Sunday, 1 p.m. ET (Fox)
Spread: San Francisco by 7
Records: Rams (Overall: 4-6-1, NFC West: 3-0-1); 49ers (Overall: 8-2-1, NFC West 2-0-1).
Past results: Two most recent meetings -- Nov. 11, 2012: Rams 24, 49ers 24; Jan. 1, 2012: 49ers 34, Rams 27.
Series record: Tied 61-61-3.
What matters: A playoff appearance seems like a foregone conclusion for the 49ers, who own a 2.5 game lead in the NFC West over the Seattle Seahawks, who will be without their two starting CBs for four games. Sunday’s trip to St. Louis presents a shot at redemption following San Francisco’s surprising 24-24 tie against the Rams on Nov. 11. Since then, the 49ers have put together two impressive victories -- first against Chicago on Monday Night Football, then on the road at New Orleans. The Rams haven’t used their good showing against the 49ers as a springboard to much more success as they backed it up with a 14-point loss to the lowly New York Jets before winning last week at Arizona. San Francisco owns a half-game lead against the Bears for the No. 2 spot in the NFC pecking order with five games left.
Who matters: QB Colin Kaepernick entered in relief against the Rams in the teams’ first meeting and has started the past two games, but it’s now clear he has supplanted Alex Smith as the team’s starter. How that changes how the 49ers' look on offense remains to be seen, but there figures to be more read-option runs with him under center and more frequent attempts to throw the ball downfield. Kaepernick’s talent is obvious, but for him the key will be consistency. He has already proved the 49ers are more dynamic offensively with him in the game, so the next step is to see if he can perform over an extended period of time.
Key matchups: Kaepernick vs. Rams secondary. Opposing teams don't have much film of Kaepernick to study, so it’ll be interesting to see how the Rams disguise their coverages in an attempt to confuse the young QB. How he responds to different teams each week could ultimately determine if coach Jim Harbaugh’s decision to go with Kaepernick is the correct one.
Roster change: The 49ers promoted LB Michael Wilhoite to the 53-man roster from their practice squad Friday. Wilhoite tweeted: “Playin n my 1st reg season game Sunday in St. Louis.. It's an honor to share the field with my teammates."
Injuries of note: TE Delanie Walker (hip, ribs) didn’t practice Wednesday and was limited in practice Thursday. K David Akers (pelvis) was a concern early in the week, but he will play. Core special teamer Darcel McBath might not play due to a concussion.
The most significant injury in the game is Rams WR Danny Amendola’s heel injury, which kept him out practice Wednesday and Thursday. He appears to be a game-time decision, but 49ers DC Vic Fangio said he’s preparing for Amendola to be available.
Inside stuff: There isn’t a staff in the NFL that makes halftime adjustments as well as San Francisco’s. Proof? The 49ers have scored 48 points on their first drives of the second half this season, which ranks No. 1 in the NFL.
Connections: Both 49ers RT Alex Boone and LB Larry Grant were roommates with Rams LB James Laurinaitis at Ohio State. Amendola and WR Michael Crabtree were teammates at Texas Tech in 2007, when they combined for 243 catches for 3,207 yards and 28 TDs.
Stats you should know: LB Aldon Smith will tie the Fred Dean’s franchise single-season sack record (17.5) with his next full sack. Smith is on pace for 24 sacks this season, which would break Michael Strahan’s single-season NFL sack record.
Looking ahead: San Francisco will host Miami on Dec. 9 before back-to-back road games at New England and Seattle. The 49ers will close their regular season on Dec. 30 at home against Arizona.
Prediction: 49ers 31, Rams 17
Follow 49ers reporter Kyle Bonagura on Twitter @CBS49ers and @KyleBonagura.
