The San Francisco 49ers are the hottest team in the NFL right now. They are also arguably the most dangerous, having strung together nine wins in a row. They look invincible, and they have a shot at maybe even stealing the top seed in the NFC. To do that, the Niners need several things to happen, but foremost on their checklist is to beat the Arizona Cardinals in Week 18 at home. A win here plus an Eagles' loss to the New York Giants would hand the NFC first seed to the 49ers. That is also huge since they would get one week's worth of rest before the divisional round. It's unlikely, but anything can happen. Now let's look at our 49ers Week 18 predictions as they take on the Cardinals.

Again, the 49ers are red-hot. They currently ride a nine-game winning streak heading into Week 18. This is especially impressive because they have been using their third-string quarterback, Brock Purdy, due to an injury to Jimmy Garoppolo. In addition, their defense has also been consistently strong, and they honestly appear to have a decent chance of making it to the Super Bowl. Of course, although they defeated the Raiders in the last game, they still need some luck in order to secure the No. 1 seed in the NFC for the playoffs. Having said that, it is surely impressive that the team has come this far considering the challenges they have faced.

With all these in mind, here are our four bold predictions for the 49ers in their Week 18 game against the Cardinals.

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4. Nick Bosa finishes with 18.5 sacks this season.

In Week 17, Nick Bosa was close to breaking the 49ers' single-season sack record that's held by Aldon Smith at 19.5 sacks. Bosa currently has 17.5 sacks so far this season, leading the NFL. Although he did not get a sack in the game against the Raiders, he was still able to contribute to the team's success by pressuring the quarterback and causing an interception.

Bosa actually leads the league in sacks and quarterback hits. He also has a much higher efficiency in tackling compared to other players with only a 6 percent missed tackle rate. Bosa is currently the frontrunner for the award for best edge rusher. He actually has twice as many quarterback hits as his closest competitor, Micah Parsons. Bosa should also be the favorite to win his first Defensive Player of the Year.

Bosa should get one more sack in this game to put him at 18.5 for the season.

3. Brandon Aiyuk goes over 80 yards

49ers receiver Brandon Aiyuk had a strong performance in the 49ers' win over the Raiders. He finished with nine receptions for 101 yards and a touchdown. He also recorded one rushing attempt for 16 yards. This was his first 100-yard receiving game of the season. Aiyuk also set new season highs in targets and receptions.

He has been a consistent contributor to the team's success and has had 74 receptions for 956 yards and 8 touchdowns so far this season. He will face the Cardinals in the final game of the season and will be a key player for the team. This is especially with both Christian McCaffrey and Deebo Samuel currently listed as questionable for Week 18. If both those guys are out, Aiyuk should be Brock Purdy's No. 1 target downfield. As such, we foresee Aiyuk getting 80+ yards and another TD catch.

2. Brock Purdy nets two TDs

In Week 17, rookie QB Brock Purdy tied the team record for touchdown passes by a rookie with 10 for the season. He had a strong second half, completing 6-of-10 passes for 113 yards on the team's final two drives of regulation. One of those resulted in a touchdown and the other which put the team in field goal range. Purdy actually finished the game with 284 yards, two touchdowns, and one interception.

He faced his first challenge of having to bring his team back from a deficit and responded well. In the process, he earned his fifth win with at least two touchdowns. We fully expect him to continue this success in a favorable matchup against the Cardinals in the final game of the season. We have Purdy going over 230 yards with two touchdowns.

1. 49ers win but stay at No. 2

The 49ers are the hottest team with a surprisingly adept rookie quarterback leading the charge. They should win their tenth game in a row at the Cardinals' expense.

As such, the 49ers have the opportunity to claim the No. 1 seed in the NFC and a first-round bye. It won't happen, though, as we also expect the Eagles to go all-out against what should be a depleted Giants roster. This means that even with a Week 18 win, the Niners will stay as the No. 2 team in the NFC.