What is it with the New England Patriots? Why must there always be an unsolved mystery after they appear in a Super Bowl? (Well, any time, really, but especially after a Super Bowl.) A year ago, everyone was wondering who had stolen Tom Brady’s jersey from the locker room. This year, the explanation for the vanishing of Malcolm Butler remains unknown and, if Bill Belichick has his way, perhaps unknowable.

The cornerback, whose interception delivered victory in Super Bowl XLIX, was MIA on the field on Feb. 4, benched for all but a special teams play despite being in on 97.8 percent of the Patriots’ regular-season snaps. It made no sense, particularly given how the Philadelphia Eagles marched up and down the field, scoring almost at will. At the time, unnamed sources speculated to NFL reporters that Butler was being disciplined for his behavior during Super Bowl week, but Devin McCourty, one of the first New England players to speak about the matter, said that wasn’t the case.

“As far as I know, all of that is the furthest thing from the truth,” McCourty told NJ Advance Media. “We all knew he wasn’t starting all week. That wasn’t a secret to the guys on the team. I get why people are fishing. The guy played 98 percent of the plays. I just hate that for him character-wise going into free agency. It’s just not true. As far as I know — and I was there all week — not one time did anything come up.”

But did teammates know why he wasn’t playing? If McCourty did, he wasn’t saying, which would be in keeping with Belichick’s passionate embrace of omerta.

“It sucked for him,” McCourty said. “He put a lot of time and effort in. However it falls, the last thing you want to do is not play a snap [on defense]. To me, the worst part was to see all that [anonymous] stuff come out after.”

Owner Robert Kraft has professed to not know the reason, either, and it may not matter if Butler departs the Patriots when free agency begins in March.

As for Butler, he’s also said he’s in the dark, but denied accusations from unnamed sources that he misbehaved.

“During my four-year career with Patriots I have always given it everything I have to play at a high-level, and would never do anything to hurt my team’s chances of winning a game, including this year’s Super Bowl where I visited with my family every night,” he wrote on Instagram. “During Super Bowl week I never attended any concert, missed curfew, or participated in any of the ridiculous activities being reported. They are not only false, but hurtful, to me and my family. Although I wish I could’ve contributed more to help my team win, I have to get ready for the next opportunity. Moving forward I will do what I have always done to work hard, and prepare for next season to be the best I can be on and off the field.”

His post drew one eyebrow-raising response. “Love you Malcolm!” quarterback Tom Brady responded in the comments. “You are an incredible teammate and player and friend. Always!”

Butler said he believes he could have changed the outcome of what became the Patriots’ third loss in eight Super Bowl appearances in the Brady-Belichick era. As for the man who could end this, he’s saying nothing.

“We put the players and game plan out there that we thought would be the best, like we always do,” Belichick said.

So the mystery lives on. At least we know what happened to Brady’s jersey.

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