Joe Douglas renewed old acquaintances before Thursday night’s Jets-Eagles preseason game, as the Jets’ newly minted general manager chatted up his former colleagues on the field. He spent some time with Eagles GM Howie Roseman, coach Doug Pederson and other coaches and players from an organization that won a Super Bowl two seasons ago, when Douglas was with the team.

Douglas runs the show now with the Jets, and what he learned from his time in Philadelphia will be hugely important in how he goes about building — and rebuilding — his new team.

Roseman was a tremendous influence on Douglas during their time together in Philadelphia, and the Eagles’ front-office boss imparted plenty of valuable lessons to his former lieutenant.

One of the most crucial: Be aggressive.

Roseman reinvented himself after losing some power during the ill-fated Chip Kelly era in Philadelphia, and his roster moves formed the foundation of an eventual championship team. It was Roseman who maneuvered up the draft board in 2016 to get Carson Wentz with the second overall pick, and he also was instrumental in bringing in Nick Foles as Wentz’s backup. Both moves paid off handsomely in 2017, with Wentz playing at an MVP-caliber level until he was felled by a knee injury and Foles doing a spectacular job in relief up to and including Super Bowl LII.

Douglas was part of the Eagles’ brain trust, and he has a Super Bowl ring for his effort. He now hopes to create a championship roster with the Jets and no doubt will be a major factor in whether this team takes the next step in becoming a playoff team . . . and perhaps a championship team.

Douglas inherited much of the current roster from former GM Mike Maccagnan, but he already has put his imprint on the team. He lured former Panthers center Ryan Kalil out of retirement, traded for Ravens guard Alex Lewis, signed former Texans tight end Ryan Griffin and traded for Colts cornerback Nate Hairston.

There almost certainly will be more to come before the Jets’ roster is finalized in time for the opener against the Bills.

Douglas indicated last week that he was happy with the current roster, but there is no question he’ll look to upgrade. He reportedly has made an inquiry into trading for Texans holdout defensive end Jadeveon Clowney, who has yet to sign his franchise tender.

Douglas has said he’d like to upgrade at edge rusher — the Jets drafted Jachai Polite, but he’s been a disappointment — so the Clowney interest isn’t a complete surprise. The one huge risk of dealing for him: He’d be working on a one-year deal.

Douglas may have a decision to make at kicker. He signed free agent Taylor Bertolet after the unexpected retirement of Chandler Catanzaro, but Bertolet has been inconsistent. He has missed two extra points, and on Thursday, he missed field goals from 53, 56 and 49 yards. You have to believe Douglas will find someone else before the opener.

With rosters being cut to 53 on Saturday, Douglas figures to be among the most active. He still needs more depth at cornerback, and in addition to a pass rusher, he can use linebacker depth after Avery Williamson’s season-ending injury and Brandon Copeland’s four-game ban.

There is plenty to like about what Maccagnan left behind, especially Sam Darnold, Jamal Adams and new addition Le’Veon Bell.

Darnold has looked particularly impressive, and perhaps Douglas will see the kind of improvement in him that he saw from Wentz in his second year. He took a gigantic step forward in 2017 and was on his way to an 11-2 record and the playoffs before being hurt in Week 14.

The Jets don’t have the quality around Darnold that the Eagles had around Wentz, especially on defense, but there’s at least a decent nucleus.

Douglas now has the chance to show his old boss and former colleagues in Philadelphia if he has the right stuff to make it big here. There’s plenty of work to be done, much of it in the coming days.