It has been a running joke in Baker Mayfield’s four-year career: The hip-thrusting franchise player with an Everyman’s comedic timing performs consistently better in TV commercials than on a football field.

Into Week 9, with the locker room’s tumult spilling out into public view and coming off a regressive loss to the Pittsburgh Steelers, the joke threatened to turn into cruel assessment: Mayfield, a former No. 1 overall pick, could entertain for a game or two, but wasn’t worth believing in.

The front office has not committed to Mayfield for the long term, as the Buffalo Bills did with Josh Allen.

His No. 1 wide receiver, Odell Beckham Jr., was released last week in a messy split in which Beckham’s father posted an 11-minute YouTube video of Mayfield failing to get his son the ball.

Adding insult to injury, Mayfield is gritting through a torn labrum in his left shoulder.

Yet Sunday was proof:

The Cleveland Browns are Baker Mayfield’s team.

In a true A.F.C. prove-it game, the Browns physically punished the Cincinnati Bengals, 41-16. Mayfield did everything he needed to do to win, passing for 218 yards on 14 of 21 attempts with a pair of touchdown passes.

All the drama that was seemingly sucking the life out of this franchise evaporated. Just like that.

Cleveland is built to frustrate 2021 N.F.L. defenses, which are universally perching two safeties deep to eliminate the big play. Instead, the Browns operate with a mentality out of the 1950s, mashing away with the run. Defenses have no choice but to respect running back Nick Chubb, who is averaging 5.8 yards per carry, and creep a safety into the box.

At which point, Mayfield is more than capable of hitting anyone deep.

The embattled quarterback busted this game open with a 60-yard touchdown heave to Donovan Peoples-Jones off play-action early in the second quarter to put Cleveland up, 21-7.

Chubb polished off this win with a 70-yard touchdown run at the start of the third quarter. Pulling guard Wyatt Teller wiped out one defender, and with a seal here (from tight end Harrison Bryant) and a seal there (from left tackle Jedrick Wills Jr.), Chubb was gone.

Peoples-Jones, too, showed massive potential, catching two of three targets for 86 yards.

On a third-and-9 from Cincinnati's 29-yard line midway through the fourth quarter, Peoples-Jones somehow hung on to the ball after taking a vicious hit from safety Jessie Bates that set the Browns up on the 3-yard line.

After an offensive holding penalty and two rushes for losses, Mayfield knifed an 18-yard touchdown pass to tight end David Njoku for the game’s final score.

Defensively, Cleveland flustered Cincinnati’s Joe Burrow, and cornerback Denzel Ward duped the second-year quarterback into an end-zone interception Ward returned 99 yards for a touchdown.

Coach Kevin Stefanski’s team can seem to resemble the Paul Brown squads of the 1950s and 1960s sometimes. They are not going to spread teams out and throw 40-plus times a game, but these Browns will bludgeon defenses with Kareem Hunt or D’Ernest Johnson or Chubb, who says about as much as players from that era, lined up at running back.

With their identity established and Beckham gone, Mayfield does not have to answer for why he tended to play better without his WR1. After the team’s trade for Beckham in March 2019 sparked hype for what could happen in the Mayfield’s second season, the Browns finished 6-10 that season.

Beckham tore his anterior cruciate ligament seven weeks into 2020 and the Browns’ offense only improved in his absence, finishing with an 11-5 record, one or two plays away from reaching the A.F.C. championship game.

Beckham’s ridiculous, one-handed catch against the Dallas Cowboys feels like a lifetime ago, and he simply never fit with Mayfield on the field. Rather than meticulously dissect the field to make the right decision, Mayfield had too often tried to placate Beckham to get him targets.

The mere presence of a star can create bad habits for any quarterback. Early in Brett Favre’s career, he would chuck it to Sterling Sharpe, which was fun and led to playoff thrills. But he gained discipline as a passer (and became a three-time most valuable player) only after Sharpe retired.

In Detroit, Matthew Stafford tended to be too reckless knowing he could throw to the Hall of Famer Calvin Johnson. And a year ago, Deshaun Watson had a career year in Houston without DeAndre Hopkins.

Now, with Beckham gone, the Browns have a shot to unlock the best of Mayfield, who serves as a singular source of energy for the team. This flag-planting, trash-talking loose cannon has turned down the turnovers, but has not transformed into a cookie-cutter quarterback who will say exactly nothing at the podium. Teammates love Mayfield’s fire, and he and the home crowd feed off each other.

The Browns can contend for a title with Mayfield, and now we know his team believes it.

‘Hero’ quarterbacks got reality checks.

The sight of Dallas Cowboys defensive end Randy Gregory smashing his helmet into the AT&T Stadium turf sure dusted off 25 years of memories. So did a vaunted Buffalo Bills offense producing all of two field goals. And the Las Vegas Raiders getting scuttled by the Giants defense.

This week also served as an open-hand slap to the face of three division-leading teams.

The Cowboys were demolished by the Denver Broncos, 30-16. And it wasn’t that close.

The Bills lost to the lowly Jacksonville Jaguars, 9-6. And it was uglier than the score implied.

The Raiders fell to the depleted Giants, 23-16. And a season full of calamities may be catching up.

All three teams are led by three quarterbacks who seemingly could do no wrong this season, be it Buffalo’s Josh Allen shucking off 270-pound defensive ends with ease, Dallas’s Dak Prescott leading a talented offense to 34.1 points per game through his six starts and Las Vegas’s Derek Carr earning M.V.P. whispers with his fourth-quarter heroics. Yet, on Sunday, all three were awful.

Allen reverted to his hero ball ways of 2018 with two costly interceptions. Prescott never found a rhythm in his first game back from a calf injury.

Carr threw two interceptions to Giants safety Xavier McKinney, one that was returned for a touchdown.

The implications are worse for the two A.F.C. upsets. The Cowboys’ offense remains capable of outscoring anyone, though Denver pounding away for 190 rushing yards points an indicting spotlight on the defense. Odds are that Dallas (6-2) will be OK in the hapless N.F.C. East as Prescott gets healthier.

It’s more complicated for the Bills and the Raiders. Despite trading their best player (linebacker Von Miller, who was acquired by the Los Angeles Rams last week) for draft picks, the Broncos (5-4) are not laying down for anyone. Teddy Bridgewater, like Mayfield, knows how to play off a dominant run game and that should scare the rest of the A.F.C. West, whose teams are separated by fractions in the standings.

Right when it seemed like the Bills (5-3) had a stranglehold on the A.F.C. East, their offense spontaneously combusted against one of the worst teams in the league. Buffalo’s top receivers could not get separation, the line was embarrassed in the trenches and Allen could not put on the Superman cape. The most troubling sign? Their nemesis, the New England Patriots (5-4), are just a half-game back in the division and peaking.

Around the N.F.L.

Patriots 24, Panthers 6: Coach Bill Belichick has yet another New England team peaking at the perfect time. New England ran 39 times, threw just 18 times and had Sam Darnold (three interceptions, 26.3 passer rating) seeing more ghosts than ever.

Falcons 27, Saints 25: Only time will tell if Atlanta did the right thing by passing on a quarterback in the 2021 draft. On Sunday, the 36-year-old veteran Matt Ryan kept the Falcons relevant. Ryan hit Cordarrelle Patterson for a 64-yard pass with about a minute left to set up a game-winning field goal. This marked Ryan’s 41st career game-winning drive, passing John Elway and Matthew Stafford for seventh on the career list.

Ravens 34, Vikings 31 (overtime): Lamar Jackson became the first N.F.L. quarterback this season to win three games after trailing by double-digits, digging the Ravens out of a 17-3, second-quarter hole with both his arm (266 yards, three touchdowns) and his legs (120 yards on 21 carries). The performance may give Jackson, the 2019 most valuable player, the edge as the front-runner to win this season’s award.

Dolphins 17, Texans 9: Hopefully nobody wasted a perfectly fine Sunday watching any of this game between two teams going nowhere.