Even better, the brash quarterback and the long suffering franchise celebrated their coming out party with a lopsided victory over a longtime nemesis.
Chubb finished with 165 yards and three touchdowns against the league's third-ranked rushing defense. Jarvis Landry had eight catches for 167 yards before leaving with a suspected concussion, and Odell Beckham Jr. had two catches for 20 yards in a supporting role.
The addition of Beckham and the maturation of Mayfield, combined with an improved defense, created high expectations for the Browns (2-2) during the offseason. Then Cleveland started 1-2, losing twice at home. Worse, Mayfield threw five interceptions and just three touchdown passes.
None of that mattered after the Browns breezed past the Ravens.
"We know how good we can be. That's the frustrating part about how we started," Mayfield said. "We just need to do our job and that's what guys did this week."
First-year coach Freddie Kitchens concurred.
"You keep your head down and keep working, usually good things happen," he said. "You turn the corner."
Cleveland kept Baltimore quarterback Lamar Jackson in check and used a mixture of Mayfield's passing and Chubb's physical running to rip the Ravens for 530 yards -- the second straight week Baltimore (2-2) yielded more than 500 yards.
"We've just got to clean it up and guys do their job. Simple as that," Ravens coach John Harbaugh said. "We're not doing our assignment the way we're supposed to, too many times, and it's costing us big plays."
Mayfield hit Landry for 65 yards and connected with Ricky Seals-Jones for 59. Then, of course, there was that 88-yard run. In all, the Browns had 10 plays of at least 16 yards.
As a result, Cleveland finds itself tied atop the division with the Ravens, who won it last year. It's the first time Cleveland has been in first place after four games since 2013.
"We haven't really won anything," Kitchens conceded. "Guys, it's just one game."
Still, it's worth noting that Cleveland went 1-15 in 2016 and 0-16 just two years ago, and this victory came against a team that owned a 30-10 lead in a series that began in 1999 -- three years after Art Modell moved the original Browns to Baltimore.
Jackson's deft passing and elusive running were a key part of Baltimore's 2-0 start, but for a second straight week he couldn't make up for his own team's porous defense. He got the Ravens to 24-18 with 9:51 left before Chubb took a pitch deep in his own territory, burst through a hole on the right side and ran untouched into the end zone.
"Anybody could have ran through that hole," Chubb said.
A subsequent fourth-down gamble by Baltimore failed before Jackson threw successive interceptions . The first one ended a run of 248 passes without being picked off.
Jackson went 24 of 34 for 247 yards and three scores. He had 66 yards rushing.
Down 17-10, the Ravens were moving for the potential tying score when Mark Ingram had the ball pried loose by Jermaine Whitehead, and Chad Thomas recovered at the Cleveland 26. It was Baltimore's first turnover of the season.
The Browns immediately went the other way and grabbed a two-touchdown advantage late in the third quarter with a 2-yard run by Chubb.
Beckham and Ravens cornerback Marlon Humphrey tangled several times during the game and got into a heated scuffle in the third quarter. Beckham threw a punch and Humphrey choked him after they wrestled to the ground. Both players were penalized.
"I ran to him after the game, apologized," Humphrey said. "That's not really the brand of football I really want to represent. When the whistle blows, it's got to be over with."
The Ravens inducted former coach Brian Billick into the team's Ring of Honor , adding his name to the facade on the upper deck. Billick led Baltimore to a Super Bowl victory during the 2000 season and went 85-67 from 1999-2007.
Browns: Starting CBs Denzel Ward and Greedy Williams were inactive with hamstring injuries for a second straight week. ... LB Willie Harvey left in the first quarter with a shoulder injury and did not return.
Ravens: DT Brandon Williams (knee) was placed on the inactive list after struggling during a pregame workout.
Browns: For the second time in three weeks, Cleveland plays in prime time, facing the San Francisco 49ers on the road Monday night.
Ravens: In the second of three successive AFC North games, Baltimore travels to Pittsburgh to face the rival Steelers (0-3 entering Monday night game vs. Cincinnati).
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