Bill Belichick joined the chorus of coaches who sing the praises of Jets defensive lineman Leonard Williams.

“A really good player, hard to block,” Belichick said this week. “You’ve got to account for him on everything, pass protection, the run game. He’s not the guy you want to give an opportunity to make a lot of plays. You’ve got to be careful with him.

“He’s got lengthy, power, quickness, athletic, plays on his feet, has a good motor, plays hard. I think he’s one of the better tackles we go against. End, tackle, he plays both. He’s one of the better guys we’ve gone against.”

Now, Belichick has been known to talk about opposing water boys like they do the job like no one he has ever seen, but his praise of Williams seems authentic and echoes what many coaches say about him.

That is why the Jets have a tough decision to make on the 25-year-old with the bushy hairdo. Do they trade him before the Oct. 29 deadline or stick with him and make a decision in the offseason on his future?

Williams is scheduled to become a free agent in March. The Jets could sign him to a long-term deal or use the franchise tag on him. But they may decide to move on in the next two weeks.

ESPN reported Sunday that multiple teams have interest in trading for Williams. The report said the Jets are not interested at this time, but coach Adam Gase did not slam the door on the idea when asked about it Monday.

Nor should Gase.

General manager Joe Douglas should explore the market for Williams. If I were Douglas, I would try to squeeze a second-round pick out of someone for Williams. Falling short of that, I would settle for a third-rounder and a lower-round pick. The Rams sent a third- and a fifth-round pick to the Jaguars last year for Dante Fowler. That seems like a good package for Williams, too.

Williams is a good player, but he is not a great one. His coaches love how he plays the run and occupies blockers to free up his teammates to make plays. Fans see a player who has no sacks this year and two in his last 16 games. He only has two multi-sack games in his career.

Jets coaches on the current staff and the previous staff say teams double-team Williams all game long, quarterbacks get the ball out fast and he is a second away from sacks. The excuses are plentiful. Basically, they say you don’t understand football if you don’t see Williams’ value.

But I have been curious to see just what Williams’ actual value will be if he ever gets to a bargaining table with the Jets. Are you going to pay him $15 million a year to do the dirty work? That money usually goes to people who sack the quarterback.

If the Jets have already decided they are not paying Williams big money, they owe it to themselves to shop him now. Defensive line is one position of strength for the Jets. They have Henry Anderson, Quinnen Williams and Steve McLendon all under contract for next year, along with some young players showing promise in Folorunso Fatukasi and Kyle Phillips.

Dealing Williams does not come without risk. I have long thought Williams would have a greater impact if he were paired with a strong edge rusher, something the Jets have not had during his time here. If you send Williams to a team with a good edge rusher, his sack numbers could improve dramatically.

Williams also is still young. While it feels like he has fully developed since he is in Year 5, he is only 25 and some defensive linemen develop later. Bill Parcells traded Hugh Douglas after a few promising years with the Jets and he blossomed into an All-Pro player with the Eagles.

Despite the risks, Douglas and the Jets need to explore the trade market for Williams. Douglas only has six draft picks right now and more holes to fill than that. Trading Williams could give him more draft ammo.

Williams comes with a stamp of approval from Belichick. Maybe the Patriots would be interested.

Ref;nypost.com