The San Francisco 49ers will take on the Los Angeles Rams in a crucial Week 18 matchup. It's time to continue our NFL odds series and make a 49ers-Rams prediction and pick.

This is a huge matchup for both of these teams. The 49ers can clinch a playoff appearance with a victory in this game, but a loss would force San Francisco to rely on other teams to push them into the postseason.

For more insight on the 49ers-Rams matchup in Week 18, listen below:

A win here clinches the NFC West for the Rams, which would in turn allow them to face the Philadelphia Eagles in the first round of the playoffs. If Los Angeles loses, there's a chance they have to face the Dallas Cowboys instead of the Eagles. Playing Philadelphia is obviously the preferred option, so a win is a necessity here for Sean McVay and crew.

Here are the odds for the 49ers-Rams game, courtesy of FanDuel.

NFL Odds: 49ers-Rams Odds

San Francisco 49ers: +4.5 (-112)

Los Angeles Rams: -4.5 (-108)

Over: 44.5 (-105)

Under: 44.5 (-115)

*Watch NFL Games LIVE with fuboTV (click for free trial)

Why The 49ers Could Cover The Spread

The Niners are one of the worst matchups in the NFL for the Rams for a couple of reasons. San Francisco's physical style of play on offense is exactly the type of attack that Los Angeles has struggled against all season long. The last time these two played, the Niners dominated the line of scrimmage, and in turn, dominated time of possession. The Rams' explosive offense was forced to stay on the sideline, and San Francisco cruised to an easy victory. It's certainly possible that the Niners take the same approach and have similar success.

While the Rams have had plenty of offensive success this season, there's reason to believe the Niners can put a stop to them. San Francisco's ability to pressure opposing passers has resulted in defensive success all year, and that should continue against a Los Angeles team that doesn't deal with pressure well. Almost every Rams loss has come against a team with a strong pass rush, and the Niners are no exception. Expect Los Angeles to have trouble keeping quarterback Matthew Stafford clean, and have trouble running their offense as a whole.

Why The Rams Could Cover The Spread

Even with their fantastic pass rush, the 49ers are a flawed defensive unit. San Francisco has been particularly bad against good opposing passing games all season long. The only passing offenses they've faced that are comparable to the Rams (besides the Rams themselves) are the Green Bay Packers and the Cincinnati Bengals. In those games, San Francisco allowed a combined 609 passing yards and four touchdowns. Stafford and the Rams should have a fairly easy time moving the football through the air here.

To make matters even worse for the 49ers defense, they're facing a plethora of injuries in this game. Starting cornerbacks Ambry Thomas and K'Waun Williams both tested positive for COVID-19, so they'll miss this contest. Starting safeties Jimmy Ward and Jaquiski Tartt are both questionable for this contest as well, and starting linebacker Azeez Al-Shaair will likely miss this game with an undisclosed injury.

Final 49ers-Rams Prediction & Pick

Los Angeles hasn't beaten San Francisco in four consecutive matchups, but they'll break the curse here. The Rams offense will be too much for a depleted Niners defense, and that will be enough for them to win by a touchdown.

Final 49ers-Rams Prediction & Pick: Los Angeles Rams: -4.5 (-108)