CLEVELAND, Ohio — Anyone who’s watched Browns quarterback Baker Mayfield sling it around in practice wasn’t shocked by his 66-yard pass to Breshad Perriman on the opening play of Sunday’s 26-20 victory over the Panthers, especially not interim coach Gregg Williams.

“His arm strength is outstanding, his accuracy is outstanding, and it probably won’t be hidden anymore after that first play of the game because that was a rocket and that was a long throw,’’ Williams said Monday on a conference call. “And it’s a long throw on the money and we’ve seen in practices, we’ve seen longer throws and we’ve seen even more accurate throws that other people haven’t seen yet, so not surprised at all.’’

Coaches, players and media have all watched Mayfield rock the passing contests in practice, where QBs heave the ball toward the goalposts or garbage cans. Doink! Doink! Doink! Mayfield always beats out Drew Stanton and Tyrod Taylor.

Because not only does Mayfield have a scary-strong arm, he’s also devastatingly accurate. You need it on the right side of the ‘8’ instead of the left side of the ‘0’? He’s got you. Even 50 yards downfield? No problem.

In fact, according to NFL’s Next Gen Stats, Mayfield had only a 15 percent chance of completing that 51-yard TD pass to Jarvis Landry in the end zone with Eric Reid draped all over him, but Mayfield’s crazy ball placement gave him a chance. What’s more, 50 yards of it was in the air.

Baker Mayfield's 66-yard pass to Breshad Perriman is now the deepest completion of the season by air yards (54.7) and 2nd-longest by air distance (63.8).#CARvsCLE #Browns pic.twitter.com/iqf9S7hsA9 — Next Gen Stats (@NextGenStats) December 9, 2018

On the 66-yarder to Perriman, which set up Landry’s 3-yard TD run, Mayfield launched it more than 62 yards in the air. In fact, according to Next Gen Stats, it’s now the deepest completion of the season by air yards (54.7) and second-longest by air distance (63.8).

As a longtime defensive coach, Williams knows just how lethal Mayfield’s combination of accuracy and strength is. What’s more, he throws astonishingly well on the run, and

“It’s very difficult (to defend) and as you continue to watch and evolve, the really, really good quarterbacks throw their receivers open in tight coverage and they have to be able to hit the very small window, the very small point of where the leverage that they have where a defender, even though in tight coverage, the defender’s there, there’s still opportunity to catch the ball,’’ said Williams. “And the best ones throw their guys open and I think you’re seeing some of that with Baker right now.’’

Williams, who’s compared Mayfield to future Hall of Fame Drew Brees whom he was with in New Orleans, isn’t stunned by Mayfield’s success over the past five games (73.2 completion %, 281.2 yards per game, 11 TDs, 4 INTs, 114.4 rating) given all their predraft due diligence, but he notes it’s also a result of his impeccable work ethic.

“He’s worked extremely hard for this success,’’ said Williams. “It’s not something that’s just happened by happenstance. The amount of work that he puts in, doesn’t shock us that he also takes it to the ballgame because he works extremely hard to have an overall understanding of every aspect of the game. That doesn’t come easy.

“I’ve been around a lot of very successful guys at that level, a quarterback at this level and we all kind of passed on some things to him what it would take and he bought into it. And don’t discount the fact he had a very good example of somebody that had — and still has — a tremendous preparation process (in) Tyrod Taylor. Tyrod learned from a lot of good people too and still Tyrod is a great mentor in that way.’’

Mayfield has already won over some analysts who might not have been 10 percent sold on him predraft, including former Browns quarterback Trent Dilfer.

“I think he can be one of the best, if not the best,’’ Dilfer told 92.3 The Fan’s Ken Carman show with Anthony Lima on Monday morning. “He’s uniquely talented. He sees the game as great QBs do.”

.@DilfersDimes on @923TheFan on how good #Browns⁠ ⁠ QB Baker Mayfield can be: “I think he can be one of the best, if not the best. He is uniquely talented. He sees the game as great QBs do.” — Keith Britton (@KeithBritton86) December 10, 2018

Hall of Fame receiver Cris Carter, who watched Browns practice on Friday and was at the game on Sunday, raved about him.

"Baker Mayfield is a version of Russell Wilson, Brett Favre, and ultimately Drew Brees. If I could have one franchise right now, be the head coach of Green Bay or Cleveland, I'm going to Cleveland." — @criscarter80 pic.twitter.com/NgxZ2dVz1M — First Things First (@FTFonFS1) December 10, 2018

Mayfield has climbed from the near bottom of the NFL to No. 21 in the league with a 93.4 rating, with three ratings of 126.9 or above in the past four weeks. He even got a compliment Sunday from his harshest critic, Fox Sports’ Colin Cowherd.

Baker Mayfield throws a better, more consistently accurate football, than Cam Newton. And it’s not close. NOT EVEN CLOSE. — Colin Cowherd (@ColinCowherd) December 9, 2018

Williams acknowledged that a lot of the Browns’ swagger right now comes from Mayfield, who engineered a fourth-quarter comeback over the Panthers, putting a TD and a field goal on the board.

“A lot of it does,’’ said Williams. “There’s guys on the defensive side of the ball, too, and there’s guys on special teams, too. But I think an awful lot of it does come from him, and that would not happen if it was phony. It only happens when everybody sees it be sincere. Leadership comes by example first and voice second and he does a really good job with that. It starts to bleed or come down or move to the team that way, and it’s good."