Nick Mullens always believed the Browns were going to have a chance to win Monday against the Raiders, no matter how dire the circumstances seemed.

Mullens, the Browns third-string quarterback, believed the Browns could win all throughout last week as COVID-19 news plucked away at the roster — and the quarterback room. He believed it as he increasingly realized he would be the starting QB in a game with serious playoff implications. And he still believed it when the game finally arrived and the offense struggled to sustain drives through the first 30 minutes.

The Browns believed they had a chance to win the entire time, too. They believed in Mullens, a four-year veteran who had been on the practice squad all season, and with 3 minutes to play against Las Vegas, that belief appeared to be coming true.

"I really believed in the fourth quarter," Mullens said, "that this night was destined for Cleveland."

Cleveland was winning by one point in the final minute of a rescheduled game Monday against the Raiders, but a final, last-second field-goal from the Raiders painfully snatched the victory from the Browns' grasp. A 16-14 loss to Las Vegas at FirstEnergy Stadium sent several players walking off the field with an emotion that had been felt all week in Cleveland.

Disbelief.

"That locker room right now is hurting," said special teams coordinator and acting head coach Mike Priefer. He served head coaching duties for Kevin Stefanski after Stefanski tested positive for COVID-19 earlier in the week. 

"That is the most I have seen it in that kind of pain," Priefer said. "You're upset when you lose. When you lose that type of game, that one is tough."

But the Browns rallied behind Mullens, who didn't know with certainty until Monday that he would start. 

The Browns were hoping for good news all weekend on QBs Baker Mayfield and Case Keenum, who were among the 20 players that remained on the reserve/COVID-19 list less than 24 hours before the 5 p.m. kickoff. The NFL rescheduled the game, which was originally supposed to be played Saturday, due to the high number of positive COVID-19 tests peppering the team, but the Browns were still unable to bring Mayfield or Keenum back for the Week 15 game.

Mullens was the next man up, and with every completion, he embodied the fight displayed by several other players needed to fill in at starting positions. Mullens went 20-for-30 recorded 147 passing yards, which led to two trips to the red zone. The Browns scored a touchdown both times — one from a 4-yard run from Nick Chubb and another from a patient, well-executed 6-yard pass from Mullens to TE Harrison Bryant with 4 minutes left.

That pass pushed the Browns ahead to 14-13 lead, a scenario that seemed unlikely to happen after they scored zero points in the first half. The Browns struggled to move the ball both with the run and the pass, but as they went into halftime, Mullens kept his composure.

He still believed they had a chance. His teammates did, too.

"Sometimes, you just kind of feel like it's your night," Mullens said. "You're like, 'We're going to finish this out. This is our thing. This is what we're going to do.' I really believed that."

The Browns got the burst they needed on the scoreboard after a 47-yard touchdown drive made possible after a fumble recovery from the defense. The distance to the end zone was cut short for Mullens, who allowed Chubb to do most of the work with a few big runs that ultimately led to a touchdown that re-electrified the fans at FirstEnergy Stadium.

Mullens felt the energy as he walked back to the sidelines, took a look at the scoreboard and realized once again that his belief all week was coming true — there was a chance. A good one, at that.

But more points were needed, and Mullens was confident he'd get them after the defense continued to keep the Raiders out of the end zone. With 12 minutes left, the offense got the ball back and paced 90 yards into Las Vegas territory for a masterful 14-play touchdown drive, made possible after Mullens scrambled to the left from the Raiders' 6-yard line, faked a sprint to the end zone to attract a defender toward him and floated the ball over him to find Bryant.

"It's kind of a monkey-in-the-middle type of game," Mullens said. "You force him to come up, and that is when you spin it to him and he opens up. That's just a good example of how to get seven points inside the red zone."

Touchdown, and then euphoria. 

But it wasn't over.

The Raiders moved the ball 51 yards on their last drive with 1:50 left and set up a 48-yard field goal from kicker Daniel Carlson. He converted on the first kick, but Priefer called a timeout to ice Carlson.

Another kick came next, and Carlson still made it.

"We came close," Priefer said. "We thought we had it."

For 60 minutes, Mullens and the Browns thought they did, too. That won't make the feeling of heartbreak any easier to stomach in the locker room, but a sense of unity was evident as players voiced their emotions.

With so many starters absent from the lineup, the odds were fully against the Browns to win. Yet they rallied behind Mullens and all the other backup players who stepped up and gave them a chance, and they plan on riding that unity to their advantage in the final three games of the season, games they might all have to win to crack a playoff berth.

"We have a lot of guys that are going to fight to the end and are not going to give up anything," Chubb said.

Mullens is one of them. Even though his first — and possibly only — start this season didn't translate to a win, he gave them a chance when one could've felt impossible to find.

"We came up short, but we had great persistence," he said. "Put it past us. Keep going. I really felt like there was more out there for us every time something happened. We're just a resilient group."