The San Francisco 49ers could be celebrating with hats and t-shirts come the end of their game with the Arizona Cardinals.

San Francisco will clinch the NFC West with a road victory over the Cardinals, which they need to maintain their position as the one seed in the conference going into the final three games of the season.

That is not something the 49ers are thinking about, however, with head coach Kyle Shanahan wary of looking past the Cardinals.

"I know we won’t be [No. 1] if we don’t handle business this week," said Shanahan. "So that’s really all we’re worried about this week and then we’ll move to who we play after that."

San Francisco 49ers (10-3) at Arizona Cardinals (3-10)
Date: Sunday, December 17
Time: 4:05 p.m. ET
Location: State Farm Stadium/Glendale, AZ
Betting odds: 49ers -12, Over/Under 48.5
How to watch on TV: CBS
Streaming: FuboTV, YouTube TV, Network apps, etc.
Radio: KNBR 680 AM / 104.5 FM, 107.7 FM “The Bone" / SacTown Sports 1140AM

Can the 49ers avoid the trap?

Everything about this week‘s matchup screams trap game for the 49ers, as they face a Cardinals team coming off a bye following a road win.

But with so much at stake, Shanahan has been very deliberate in his messaging to his team, telling them to ignore Arizona’s 3-10 record and labeling it as a playoff game for the Niners. If the 49ers want to be able to celebrate a division win this week and stay in control of the one seed race, they must heed his words.

A stern defensive test

The 49ers' defense held Jalen Hurts in check on the ground two weeks ago in their blowout win over the Philadelphia Eagles. 

Now they get another test from a dual-threat quarterback in Kyler Murray. San Francisco is 3-2 against Murray in his career, but the former number one overall pick has traditionally caused the 49ers problems with his ability to extend plays and make an impact as a runner.

His dual-threat ability is the most likely equaliser in what otherwise looks to be a mismatch. San Francisco kept Hurts in the pocket and forced him to hold the ball in Week 13, and it’s imperative the 49ers’ defense does the same to Murray to avoid an upset in Week 15.

3 Players to watch

• QB Brock Purdy: It's a homecoming for the Arizona native, who will be under pressure to keep an explosive offense firing on all cylinders to ensure the 49ers are protected if the defense struggles against Murray and simultaneously maintain his place at the front of the MVP race.
• LB Dre Greenlaw: Beyond the defensive line keeping contain, it is the 49ers' linebackers who have the biggest role to play in shackling Murray as a runner. Excellent in the open field but banged up with ankle and hip injuries, the Niners can't afford Greenlaw to be anything other than his best if they are to prevent the Arizona quarterback from being a leveler.
• CB Ambry Thomas: Sixth in Pro Football Focus coverage grade among cornerbacks since Week 10, Thomas may start on base downs as well as nickel downs this week with Charvarius Ward questionable with a groin injury. Facing a speedy receiver group led by Marquise Brown and Rondale Moore, he must maintain his recent strong form.

More 49ers news ahead of the game

• 49ers make roster moves that point to potential good injury news
• Kyle Shanahan dispels lazy narrative around the 49ers' defense

49ers’ Brock Purdy under the microscope in Week 15 homecoming

San Francisco has a huge opportunity.