Malcolm Butler closes in on Amari Cooper. (Tom Pennington/Getty Images)

It was the biggest mystery of Super Bowl LII. How on earth was Malcolm Butler, the hero of the New England Patriots’ Super Bowl victory in 2015 and a man who had started 15 regular season and two playoff games, sitting on the bench with the Patriots and Philadelphia Eagles battling down to the wire?

It was a mystery that had only grown in the months that followed, with Patriots Coach Bill Belichick unwilling to discuss his decision, players such as Tom Brady and Danny Amendola trying to parse it, Butler unable to offer an explanation and, finally, the Patriots allowing Butler to walk in free agency.

The story line was resurrected this week, with no real clarity, because Butler’s new team, the Tennessee Titans, host the Patriots on Sunday, and both he and Belichick are moving on.

“It’s just another game,” Butler said (via the Tennessean).

The cornerback has struggled since leaving New England, and he allowed eight of 11 passes against him to be completed for 108 yards and two touchdowns in the Titans’ 28-14 victory over the Dallas Cowboys on Monday night. Overall, he has given up the most receptions, yards and touchdowns in the league, and quarterbacks have a 141.8 passer rating against him (via NESN).

“Eye control and just do the little things,” he said. “It’s only the little things that are affecting me. It is what it is. Got to keep playing, man.”

Belichick didn’t care to revisit the Super Bowl or to comment on Butler’s struggles. “That means a lot to me,” Belichick said sarcastically when Butler’s stats were mentioned.

Belichick was asked what he had seen from Butler and Logan Ryan, another former Patriots player, and was no less snarky.

“They lead the league in defense, so they’re good,” Belichick said. “They don’t give up big plays.”

The Titans are the NFL’s stingiest team, giving up only 17.6 points per game, and they’re eighth in total defense (333.5 yards per game).

“They lead the league in defense, okay? So, that’s our challenge as an offense is, we’re playing 11 guys,” Belichick said. “We’re playing their coaching staff and the schemes they put up against us. Right now, they’re playing better defense than anyone else in the league. We’ll see how we do. I don’t know. It will be tough, I know that.”

Whatever their relationship, Butler told ESPN.com over the summer that there was “no bad blood” between the two and that Belichick had called to thank him after he signed with Tennessee. “One of the greatest coaches ever, and I care about him. I know he care about me,” Butler said. “And this a hurtful game sometimes, and it can look different than what it is. But that’s my guy. . . . I got a lot of respect for him.”

Read more from The Post:

Alabama fan dies from injuries sustained in bar fight after LSU game

‘Harper’s bazaar has begun,’ and so has the Scott Boras Show

ESPN’s Stephen A. Smith says the Wizards' situation is an ‘abomination’ and a ‘disgrace’

Le’Veon Bell is back in Pittsburgh but still tweeting rather than reporting to the Steelers

Floyd Mayweather says he ’never agreed to an official bout’ with Japanese fighter

A greyhound racing ban in Florida means thousands of dogs will need homes