MJ Stewart Jr. never doubted his playmaking ability when he learned in Week 15 that he'd be taking a sizable role in the defense.

Stewart, a four-year veteran who had largely been a special teams player for most of the season, was being called to start for a defense that had been depleted by positive COVID-19 tests and injuries. Troy Hill and Greg Newsome II, two players who had handled slot cornerback duties, were out for the game against the Raiders. At safety, Grant Delpit and Ronnie Harrison Jr. were both on the reserve/COVID-19 list.

Stewart was capable of playing both safety and cornerback, which made him the next man up.

"The only thing that came to my mind was 'it's my time now,'" Stewart said Tuesday to local reporters on a Zoom call. "That's literally the only thing, and just take advantage of this opportunity. With football, you never know how many opportunities you're going to get. You don't know when your next one is coming."

Stewart has undoubtedly seized the opportunity in the last two games. He's played in all but two defensive snaps and leads all Browns players with 21 tackles in that stretch, and he's helped the defense, which ranks seventh in the league in total defense, stay strong despite the Browns navigating through unexpected, COVID-19-related absences at several positions.

Stewart has delivered just as the Browns have hoped, and they're going to keep relying on him as they push for the playoffs in the final two regular season games. His versatility — and recent stretch of efficient tackling and adhering to his assignments — demands it.

"MJ has been stepping up big time," CB Denzel Ward said. "He has double-digit tackles, and he has been all over the field. He's been a great player for us, and we're going to need him this week, as well."

The Browns are still awaiting to activate Newsome from the reserve/COVID-19 list, which could lead to Stewart holding another big role in Week 17 against the Steelers. Hill, who was activated from the reserve/COVID-19 list Monday, is also recovering from a knee injury and has uncertain status for the game as well.

Stewart, though, has provided plenty of evidence that he can continue to handle a big role. He dealt several heavy hits and showed sound tackling skills with 10 tackles — nine of which were solo takedowns and two of them were tackles for a loss — Saturday in Green Bay, and he helped limit slot WR Hunter Renfrow to just three catches for 32 yards when he was tasked with a slot corner role against Las Vegas. Stewart holds a serviceable 76.2 grade from Pro Football Focus this season.

"That's just how my whole career has been," he said, "just being ready to take advantage of any opportunity I get."

Stewart, a 2018 second-round pick who spent his first two seasons in Tampa Bay, opened himself up to several opportunities over the last two weeks with his versatility. His range and footwork have enabled him to play both cornerback and safety, which Stewart hasn't played since his high school days at Yorktown High School in Arlington, Virginia. He's been asked to play both positions in the last two weeks and has looked like a true veteran, reading plays accordingly and showing no fear in lowering the shoulder to drop a big hit.

"I just take pride in being versatile," Stewart said. "I've always kind of been a smart player. It was really mental, just making sure I knew all of the checks and everything like that."

No play from Stewart's Browns career, though, has been as big as the play he made in the Wild Card game against the Steelers last season.

He was the first of four Browns players to record an interception off Pittsburgh QB Ben Roethlisberger to give Cleveland a stunning, dominant 35-10 lead at halftime. The game was the first playoff contest of Stewart's career, but the stage wasn't too big for him to make one of the biggest plays of the night.

"It was a rollercoaster for sure, but it was fun," Stewart said. "Just getting a chance to put your skills on display, being out there with guys, just having fun and making plays. You live for moments like that when you're a football player."

The Browns return to Pittsburgh on Monday for the first time since that game, and it comes with another playoff-like setting — the Browns must win against the Steelers and win again against the Bengals in Week 18 to have a chance to crack the postseason. They also need the Chiefs to defeat the Bengals on Sunday and for the Ravens to lose one of their last two games against the Rams or Steelers to win the AFC North.

"Our focus is just going 1-0, honestly," he said. "Everybody knows what this game means to us."

Stewart proved he can do what's needed to ensure the Browns have a chance to win. He's ready for the call again, if the Browns need him to once again take a near every-down role in their defense.

He's never doubted himself to step up and fulfill it. Now, after two weeks of dominant play, he feels even more prepared and confident to keep at it.

"We all believe in each other," he said. "We all know what each other can do. When somebody gets their time and they do what they are supposed to do and make plays, we're all happy for each other."