With the 2022 NFL preseason in full swing, we have some idea of what rosters are going to look like this year. Many position battles remain unsettled, but the core players and key pieces have been established.

The reality, though, is that surprises emerge every year to make their teams substantially better. These X-factors can come be undervalued rookies, players returning from injury, former backups in starting roles and those breaking out of slumps.

In 2021, for example, Cincinnati Bengals quarterback Joe Burrow returned from a torn ACL to lead his team to the Super Bowl during his sophomore campaign. The Chicago Bears didn't enjoy the same success, but defensive end Robert Quinn bounced back from a dismal two-sack season to tally 18.5 quarterback takedowns.

Here we'll examine one X-factor for each NFL team. These aren't highly touted rookie first-round picks or players coming off Pro Bowl or All-Pro campaigns. However, each one listed has the potential to positively impact his team's record in 2022.

 

Arizona Cardinals: WR Marquise Brown

The Arizona Cardinals won't have star receiver DeAndre Hopkins for six games this season, as he has been suspended for a violation of the league's performance-enhancing drugs policy. For at least a stretch, quarterback Kyler Murray will need a new top target.

It could be wide receiver Marquise Brown, who was acquired from the Baltimore Ravens in a draft-day trade. A first-round pick in 2019, Brown never quite developed into a No. 1 option in Baltimore. However, he was a 1,000-yard receiver last season and played at Oklahoma with Murray.

With Murray at quarterback in 2018, Brown caught 75 passes for 1,318 yards and 10 touchdowns.

If the two can rekindle their college chemistry, Arizona will have another big-time weapon to go with Hopkins (when available), A.J. Green and tight end Zach Ertz. If Brown is the player we saw with the Ravens, he'll be a fine complementary deep threat but may not drastically impact the passing attack. He may merely serve as a replacement for departed free agent Christian Kirk.

The caveat here is that Brown was arrested on criminal speeding charges earlier this month and could face league or team discipline.

 

Atlanta Falcons: QB Marcus Mariota

The Atlanta Falcons traded longtime starting quarterback Matt Ryan to the Indianapolis Colts this offseason. They brought in 2015 first-round pick Marcus Mariota, who was quickly named as the starter over rookie third-rounder Desmond Ridder.

"Obviously, we've got a plan for each of them. Marcus is the starter," quarterbacks coach Charles London said following Atlanta's first practice of camp, per Josh Kendall of The Athletic. "That's how we're going into this thing."

We saw flashes of promise from Mariota during his time as the Tennessee Titans' starter. He helped take Tennessee to the playoffs in 2017. If he can be a steady presence under center, Atlanta could surprise in 2022.

If Mariota flounders, however, he'll likely give way to Ridder at some point in the season. If and when that happens, the rest of the Falcons' campaign will be about evaluating and developing the University of Cincinnati product.

Mariota is an X-factor because his play will determine Atlanta's goals and its direction over the next several months.

 

Baltimore Ravens: RB J.K. Dobbins

While Mariota is looking to revitalize his career, the Ravens know they have something special in quarterback Lamar Jackson. Staying healthy will be key for the Louisville product, who missed five games last season because of illness and an ankle injury.

However, Baltimore will want to support Jackson with a strong ground game. That proved difficult in 2021, as running backs J.K. Dobbins (ACL), Gus Edwards (ACL) and Justice Hill (Achilles) all suffered season-ending injuries before Week 1.

A lot will hinge on Dobbins' recovery, as the 2020 second-round pick showed loads of potential as a rookie. He finished with 805 rushing yards, a 6.0 yards-per-carry average and nine touchdowns on the ground.

Dobbins can be Baltimore's bell-cow back if he's back to pre-injury form early in the season. He isn't there just yet.

"How he does in the next week to two weeks, to me, is going to tell the story," head coach John Harbaugh said, per Kevin Eck of the team's official website.

If Dobbins can help Jackson lead a potent rushing attack, the Ravens should be right back in the thick of the AFC North race. If he can't, the team may have to get creative on offense.

 

Buffalo Bills: Edge Gregory Rousseau

The Buffalo Bills made a big offseason splash when they signed star pass-rusher Von Miller to a six-year, $120 million deal. Miller, who had four sacks in four postseason games for the Los Angeles Rams last year, should further boost a Bills defense that ranked first in yards and points allowed in 2021.

While the defense was stout last season, it often had to get creative to produce sacks. The Bills had 42, but Mario Addison led the team with only seven. No other player had more than four takedowns, and Addison departed in free agency.

If Buffalo hopes to field an elite pass-rushing tandem, it needs to see more out of 2021 first-round pick Gregory Rousseau. The Miami product showed flashes as a rookie, with four sacks and 24 quarterback pressures, but he isn't yet the elite complement to Miller that the Bills need.

Rousseau logged just one sack in his final 12 regular-season games and none in the playoffs.

If Rousseau is able to take the next step as a sack artist, the Bills should have a potent pair of pass-rushers who are capable of harassing quarterbacks on their own. If he can't, Buffalo may have to continue rotating rushers and bringing extra defenders on the blitz.

 

Carolina Panthers: QB Baker Mayfield

The Carolina Panthers stumbled to a 5-12 record last season despite having a new quarterback in 2018 third overall pick Sam Darnold. Injuries to star running back Christian McCaffrey (hamstring, ankle) played a role, but the former New York Jets signal-caller posted a paltry passer rating of only 71.9.

This offseason, Carolina traded for 2018 first overall pick Baker Mayfield. Mayfield also had a poor and injury-impacted 2021 campaign (83.1 rating), but he's accomplished far more in the NFL than Darnold.

In 2018, he set a since-broken rookie record with 27 touchdown passes. In 2020, he led the Cleveland Browns to their first playoff win as an expansion franchise. If he can elevate the Panthers' quarterback play, the team should at least be relevant in the NFC South.

First, though, he'll have to beat out Darnold, and after one preseason game, it's still too close to call.

"They were both in command," head coach Matt Rhule said after the 23-21 victory over the Washington Commanders on Saturday, per Stephen Whyno of the Associated Press. "Sam got us in the end zone. Baker led us down the field. So it looked like both guys played well in terms of production."

If Mayfield can win the job and play like the quarterback he was in 2018 and 2020, the Panthers could be dangerous. If he fails to do both, Carolina will most likely be irrelevant again.