CLEVELAND — Four days before Cleveland Browns quarterback Jameis Winston was set to make his first NFL start in more than two years, he offered a confident assertion.

“I view this as an opportunity to go out there and be my very best,” Winston said Wednesday. “And when I’m my very best, I’m a great NFL starter.”

Winston backed up that talk Sunday, throwing the game-winning touchdown in the Browns’ 29-24 upset victory over the Baltimore Ravens to end a five-game losing streak. It was Cleveland’s first game since losing starting quarterback Deshaun Watson to a season-ending Achilles tendon tear.

Winston did his part in injecting life into a Cleveland offense that had been one of the NFL’s worst through seven games.

He completed 27 of 41 passes for 334 yards — a franchise record for a quarterback in a Browns debut — and three touchdowns, including the 38-yard, go-ahead score to wide receiver Cedric Tillman with 59 seconds remaining.

“I thought he played well,” Cleveland coach Kevin Stefanski said of Winston. “I thought the protection was outstanding all day. The guys really took the challenge of that, and I thought he got through his reads and guys got open. He made good decisions. Wasn’t perfect. He’s not going to play perfect. I’m not going to coach perfect. But I thought he played well.”

With Stefanski handing playcalling duties to offensive coordinator Ken Dorsey, the Browns had a rhythm and a flow it lacked all season with Watson under center. Cleveland (2-6) reached 20 points for the first time all season and set season-high marks for passing yards, total yards and third-down conversion rate.

A passing offense that was disjointed suddenly became explosive. Winston recorded eight completions and two touchdowns on passes that traveled at least 15 yards downfield, according to ESPN Research, including the winning toss to Tillman. Watson had just nine such completions and one touchdown in the seven previous games.

“He brought great energy,” Tillman said. “Jameis kept telling us that he’s going to keep throwing it. He’s going to keep coming back to us no matter what. He played great today.”

Winston, the No. 1 pick in the 2015 draft, was making his first start since Sept. 25, 2022, when he was a member of the New Orleans Saints. It didn’t come without mistakes and scares. He lost a fumble on a sack late in the first half that led to a Ravens touchdown and put the Browns behind 10-6 at halftime. He twice avoided interceptions on drops by the Ravens (5-3), including what could have been a game-sealing interception when he overthrew wideout Elijah Moore that safety Kyle Hamilton couldn’t corral.

Winston, though, was unfazed, finding Tillman downfield on the very next play as the Ravens’ blitz was barreling down on him.

“Ken always talks about how we’re not going to be conservative,” Winston said. “We’re going to be aggressive and not conservative. And that’s the way he preaches as an offensive coordinator. And that’s what we showed, that’s what we exemplified out there on that field today.”

Winston, known for being an animated figure in the Browns’ locker room, addressed his teammates in a passionate pregame speech, emphasizing the need to have “unwavering faith.”

And in his first start as a Brown, Winston was unflappable, down to his winning throw.

“I am certain when I am making great decisions one play at a time I am a great NFL quarterback,” he said after the game. “I am certain of that.”