Bill Belichick has not been open in offering details about who will be the New England Patriots’ defensive play-caller in 2019. In fact, Belichick wouldn’t even confirm that linebackers coach Jerod Mayo has been calling plays to this point.

Mayo, a first-year assistant coach and retired Patriots linebacker, was wearing the headset and carrying the play chart in Week 1 of the preseason, just like he has done in summer and spring practices.

Patriots safety Duron Harmon confirmed what was immediately apparent.

“Jerod, obviously, he’s been calling the plays for us,” Harmon said on Monday during a radio appearance on WEEI. “He’s been working at making sure he can get the play in on time and he’s been doing a good job for us. Obviously, there are going to be growing pains, and I wouldn’t even call them growing pains. There are just some things we’re going to need to get better at, but right now I like where we are headed.”

The question is whether Bill Belichick will take over as a play-caller or whether Mayo might continue working the role. There have been reports that Belichick intends to take over the position. But he has yet to take the headset, and he’s been extremely cagey about the topic. He was asked Friday whether Mayo is calling plays or whether it’s a team effort at this point.

“We’ll always do what we feel is best for the football team,” Belichick said. “That’s what we always do, so I don’t see that really changing.

So … is Mayo calling defensive plays?

“We’re doing what’s best for the football team,” Belichick said.

Harmon, of course, clarified things a few hours later.

It was Mayo’s first test actively calling plays during a game setting. He had previously been calling them during practices, but he was working off a script, which was designed for that specific practice. Belichick was asked Monday what goes into good defensive play-calling in a game.

“Well, look, everything – whatever phase of the game it is – defensively, it’s about team defense,” Belichick said. “It all centers around that, what the team can do effectively and who we’re matched up against and so forth. It’s a combination of a lot of things.”

It will be worth monitoring whether Belichick takes the headset for any of the preseason games.

Gallery Grading the Patriots rookies' preseason debut vs. Lions View 11 photos

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