NFL quarterbacks face nonstop criticism. Playing the most important position, the QB often carries the lion’s share of the blame following a loss. In a league known for its ‘what have you done for me lately’ mantra, quarterbacks are so often judged on their most recent body of work.

There is no shortage of QBs facing it make-or-break seasons in 2020. Here are the five quarterbacks with the most to prove in the upcoming NFL season.

5. Drew Lock, Denver Broncos

Denver Broncos president of football operations John Elway has put his trust in Drew Lock to become the new face of the franchise. Lock, a second-round pick in 2019, started five games in his rookie season.  He posted a 4-1 record and completed 64 percent of his passes for 1,020 yards, seven TDs and three interceptions.

Emphasizing a retool of their offensive arsenal this offseason, the Broncos signed two-time Pro Bowl running back Melvin Gordon. They selected wide receivers Jerry Jeudy and K.J. Hamler in the first and second rounds, respectively.

Lock already had Pro Bowl wideout Courtland Sutton and talented tight end Noah Fant at his disposal, so the additions of Gordon, Jeudy and Hamler give the Broncos a treasure trove of weapons. If the offensive line holds up, Lock will have no excuses if the Broncos fail to deliver a high-octane offense.

The Broncos have not made the playoffs since their 2015 Super Bowl season. The failure of the quarterback has been most to blame. In addition to Lock, Paxton Lynch, Trevor Siemian, Brock Osweiler, Case Keenum, Joe Flacco and Brandon Allen have started games at QB. Lock needs to perform better than his predecessors to maintain the starting signal-caller job in Denver.

4. Jarrett Stidham, New England Patriots

Jarrett Stidham is now the man under center in New England. Following the free-agency departure of Tom Brady, the Patriots decided to hand the keys to the franchise over to Stidham.

The Patriots opted against drafting a QB. They brought back veteran backup QB Brian Hoyer and signed undrafted rookie J’Mar Smith, but Stidham is the undisputed starter.

It’s a daunting task following in the footsteps of the greatest quarterback of all time, but Stidham does have the advantage of playing with a dominant defensive unit. Cornerback Stephon Gilmore won the Defensive Player of the Year honors last year, helping the Patriots finish with the top-ranked defense.

Despite losing linebackers Kyle Van Noy (Miami Dolphins) and Jamie Collins (Detroit Lions) in free agency, their Bill Belichick-led defense is still expected to be among the NFL's best.

The Patriots’ offense was mediocre last season and they still managed to win 12 games and capture their 11th consecutive division title. Even if Stidham only plays mediocre, there’s still a chance the Patriots could reach the playoffs again. Even so, all eyes will be on Stidham to determine if he can be the next mainstay QB of the Patriots.

3. Gardner Minshew, Jacksonville Jaguars

Jacksonville Jaguars head coach Doug Marrone has maintained all offseason that Gardner Minshew is the team’s starting quarterback entering 2020. Anything beyond this upcoming season, however, remains up in the air.

Minshew was the lone ray of hope during last year’s disastrous six-win season, as the rookie QB threw for 21 TDs against just six interceptions. He excelled in throwing deep passes.

And yet, Minshew’s fate is far from secure, especially since the general manager who drafted him, Dave Caldwell, is on the hot seat in Jacksonville.

The Jaguars are seen by many as one of the worst teams in the NFL. It’s hard to imagine them improving after trading away star defensive end Calais Campbell and cornerback A.J. Bouye over the offseason. The onus will be on the Jaguars’ offense—which mustered just 18.8 points per game last season—to carry the team in 2020.

If the Jaguars struggle as projected, the team could look for a fresh start in the front office. Assuming that happens, the new regime may look to grab a quarterback in the draft, especially if Clemson’s Trevor Lawrence or Ohio State’s Justin Fields are available. As such, the deck appears stacked against Minshew, putting enormous pressure on him in 2020.

2. Baker Mayfield, Cleveland Browns

The No. 1 overall pick of the 2018 NFL Draft, Baker Mayfield set a league-record with 27 touchdown passes in his rookie campaign. Following last offseason’s addition of star wideout Odell Beckham, the Cleveland Browns entered the 2019 season as the favorites to win the AFC North crown.

Mayfield and the Browns fell far short of expectations, winning just six games. Even more disconcerting, Mayfield regressed during his sophomore year. He had nearly as many interceptions (21) as TDs (22) and the offense never gelled, despite the plethora of playmakers.

The Browns bolstered their offensive line by signing tackle Jack Conklin and selecting Jedrick Wills in the first round of the draft. They also added two-time Pro Bowl tight end Austin Hooper during NFL free agency. There's no denying Cleveland has provided Mayfield plenty of talent to work with.

Mayfield needs a bounce-back season in 2020 to demonstrate why he should stay under center in Cleveland.

1. Mitchell Trubisky, Chicago Bears

The Chicago Bears are putting the pressure on Mitchell Trubisky to perform in 2020. They traded for former Super Bowl MVP Nick Foles and then declined Trubisky’s fifth-year option. Foles will challenge for the starting QB duties, though the job remains Trubisky’s job to lose.

Trubisky’s widely-documented accuracy issues became a major problem for the Bears last season. Chicago managed to disguise his deficiencies as a passer the prior year with gadget and trick plays, but those can only work for so long.

The Bears’ 25th-ranked passing offense mustered just 205 yards per contest. Trubisky’s completion percentage, TD passes and passer rating took a nosedive in 2019. The Bears finished with an even 8-8 mark last year, missing the postseason despite high aspirations.

Chicago traded up to draft Trubisky in 2017, bypassing Pro Bowl signal-caller Deshaun Watson and Patrick Mahomes, the reigning Super Bowl MVP. It’s highly unlikely Trubisky can ever come close to playing at the level of Watson and Mahomes, but he still has time to reaffirm his status as the Bears quarterback of the future.

However, the leash will be short on Trubisky this year, unlike in previous seasons, and a rocky start to 2020 could easily end his tenure as Chicago’s QB.