REUNION TO WATCH

When the 7-2 Patriots play the 4-4 Titans on Sunday, there will be a lot going on in the way of subplots.

The Patriots will be facing their Super Bowl XLIX hero, cornerback

Malcolm Butler, who signed a $61 million free-agent contract ($30 million guaranteed) with Tennessee in the offseason.

They, too, will be facing Titans head coach Mike Vrabel, who was a three-time Super Bowl winner as a linebacker in New England.

Butler has not lived up to his contract or his reputation as a shutdown corner so far this season. The 28-yearold has allowed an alarming seven TD receptions already — half the total number of touchdowns the Titans defense has allowed all season.

That number is the worst among NFL cornerbacks, according to Pro Football Focus. So, too, are the 39 catches and 618 passing yards he’s yielded.

In last week’s Titans 28-14 win over the Cowboys, Butler allowed eight completions (on 11 targets) for 108 yards and both of the Cowboys’ TDs. Vrabel, who was traded by Bill

Belichick to the Chiefs in 2009, said he and the Patriots coach “didn’t talk for a couple months, maybe a year” after the transaction.

“Then we became friends, and I used him as a resource when I started my coaching career, and still talk to him a lot now,’’ Vrabel said. “This week we’re competitors.”