Giants head coach Brian Daboll, right, embraces Bills wide receiver...

Giants head coach Brian Daboll, right, embraces Bills wide receiver Stefon Diggs prior to an NFL game in Orchard Park, N.Y., on Sunday. Credit: AP/Adrian Kraus

The coach and his quarterback walked out of Highmark Stadium in Buffalo on Sunday night shoulder-to- shoulder after a hard-fought contest, chatting and smiling about the previous 3 1⁄2 hours of gamesmanship and athletic displays.

As they made their way through the crowd, they would turn and look to make sure the other was still there. They seemed happy to have such a strong connection, one that has served each of them handsomely in the past.

Then they said goodbye.

Brian Daboll got on the Giants’ team bus to head back to New Jersey and Josh Allen headed toward his ride home somewhere in Western New York after rekindling their close friendship for at least a few minutes in the wake of the Bills’ 14-9 victory.

They’d sought each other out for that quick stroll together. It was a reminder of how fond the two men are of each other, how they were able to bring out the best in one another during their simultaneous tenure back when Allen was a young, developing quarterback and Daboll was his offensive coordinator.

It also was a reminder that it’s easy to be a genius coach when you have a top-tier quarterback — and a little harder to convince folks you deserve that title when you don’t.

Daboll, whose record as a head coach with the Giants fell to 11-13-1 (including two playoff games) since leaving Allen and Buffalo, certainly isn’t alone among coaches who are suffering from quarterback separation anxiety. The most glaring example of it resides at another of Daboll’s former places of employment, New England, where the greatest coach in football history has been reduced to the level of a buffoon since losing the grip on his magic feather.

Did Bill Belichick forget how to coach? No. He’s just not as good at it without Tom Brady on the field.

Nor is Sean Payton as good a coach as he was with Drew Brees. Mike McCarthy and Matt LaFleur have looked lost without Aaron Rodgers. At least Andy Reid gets to keep grinning.

Daboll wasn’t outcoached by Sean McDermott on Sunday night. If anything, it was the opposite. Daboll and defensive coordinator Wink Martindale seemed to have answers for just about everything the Bills wanted to do on both sides of the ball.

Allen was the difference in the game. The Giants were out-quarterbacked.

That they were playing with their backup, Tyrod Taylor, made the difference even more pronounced. And Taylor certainly didn’t do his coach any favors by running the ball with 14 seconds left and no timeouts at the Bills’ 1 at the end of the first half. It was the wrong choice 100 out of 100 times.

Then again, if Saquon Barkley had scored, it might have been heralded as heads-up, unorthodox, outside-the-box, free-wheeling, aggressive football .  .  . the kind for which Daboll supposedly is known and admired.

At some point in the coming weeks, Daboll will get his starting quarterback back from the neck injury that sidelined him for Sunday’s game. Daniel Jones, once medically cleared, will assume his spot as the team’s top option. Daboll is so committed to that hierarchy that when asked Monday if there might be a shred of hesitation to return to Jones, he had to have the question repeated in various ways to even understand it. Once he did, he scoffed at the very notion.

“Pfft,” he grunted. “No.”

But Jones wasn’t able to get the offense into the end zone in the two games before Sunday’s when he was healthy, and it’s becoming at least a conversation about whether he is, in fact, the long-term solution to the Giants’ search for a championship quarterback.

It was Jones’ play last season, particularly toward the end and in the playoffs, that helped lift Daboll to his Coach of the Year award. This year it has been Jones’ play, addled as it has been by the terrible showings of the offensive line and playmakers around him, that pretty much has ensured that Daboll won’t be a repeat winner.

Daboll’s friendship with Allen undoubtedly will continue. The two of them speak regularly via FaceTime talks and texts, catching up on their personal lives as well as football. And they had those sweet few minutes to reconnect in person after Sunday’s game. They were, for a blink at least, transported back to the coach-quarterback connection that warmed them personally and elevated them professionally.

Once they reached the end of that tunnel, the two went on separate paths. Allen and the Bills were off to see if they finally can win a Super Bowl for Buffalo. Daboll returned to East Rutherford to scrounge for solutions for his 1-5 team, perhaps aware that he’d just said goodbye to the exact thing he and the Giants seem to be missing the most.

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