CLEVELAND -- On fourth down inside the Denver 10-yard line, Cleveland Browns quarterback Case Keenum dropped back with the Denver Broncos' pass rush barreling down on him and no place to throw the ball.

So Keenum took off up the middle. And with a Denver linebacker standing in the way, Keenum faked left, then dove right for a first down at the 1-yard line. Then, on the next play, he lofted a touchdown pass off play-action to help propel the Browns to a 17-14 victory over the Broncos Thursday night.

Two offseasons ago, the Browns didn’t just sign Keenum to be a mentor for starting quarterback Baker Mayfield. They brought him in believing he could come through in a pinch, to keep Cleveland’s season afloat if called upon. With Mayfield out because of a torn labrum and a tuberosity fracture in his left non-throwing shoulder, Keenum delivered on Thursday night at FirstEnergy Stadium.

"He fought like he always does," Browns coach Kevin Stefanski said of Keenum. "Orchestrated the operation. That was a huge play there on fourth down. Just to make a play, fighting for extra yardage. He did a great job fighting."

Operating efficiently out of a heavy play-action-based, short-throw-oriented attack, Keenum steadied the Browns following two consecutive losses. He completed 21 of 33 passes for 199 yards and the touchdown, which followed the play of the game -- his fourth-down conversion.

“You don’t have to get ready if you stay ready,” Keenum said this week, “and I’ve been ready since I got here.”

Keenum may have to stay ready for the time being.

Complicating Cleveland’s quarterback situation further, Mayfield disclosed he also has a fracture in his left shoulder. Mayfield is aiming to return by Cleveland’s next game on Oct. 31 against the Pittsburgh Steelers.

But if Mayfield is unable to go, Keenum proved Thursday that the Browns have another quarterback who can deliver.

Buy on a breakout performance: With Nick Chubb and Kareem Hunt both nursing calf injuries, third-string running back D'Ernest Johnson made the most of his first career start. Johnson rushed for 34 yards on the opening drive, including a 4-yard touchdown run. Johnson went on to finish with 146 yards -- the first 100-yard game of his career. Chubb could be back as soon as Oct. 31. But with Hunt expected to be out multiple weeks, Johnson showed he can keep Cleveland’s powerful rushing attack humming.

Troubling trend: The Browns defense dominated for much of the game, holding Denver to 76 total yards in the first half. But in the second half, Cleveland’s defense had multiple opportunities to put Denver -- and its lackluster offense -- away. Instead, the Broncos were able to engineer a fourth-quarter touchdown drive to keep the game interesting. The Browns still boast the talent to field a top-tier defense. But halfway through the season, they still have yet to put it all together.

Describe the game in two words: Get right. It wasn’t the prettiest performance, but the Browns desperately needed this victory to keep their lofty preseason aspirations intact.