"I know he just loves ball in its simplest form, so I threw it all out to him, whatever he wanted to do, [including defensive coordinator]," Shanahan told The Athletic's Tim Kawakami last month. "I was like, 'Would you be interested?' And he was very nice and appreciative, and he politely turned me down."
This week, Belichick appeared on "The Pat McAfee Show" and was asked about the job offer. Unsurprisingly, he declined to reveal any details of his discussions with Shanahan.
"I appreciate the question," Belichick responded. "I'm just going to keep all those conversations that I had between any other coaches or teams or whatever, just, we'll keep those private. I appreciate the conversation."
Belichick went on to praise Shanahan and his work as an offensive innovator.
"Kyle's great," Belichick said. "I love Kyle. A ton of respect for him, his dad, and the way they coach the game, what they've done for the game. I love Kyle and Mike Shanahan, and I think they do a tremendous job. But they'll just leave our personal relationship aside on that one.
"But I studied them a lot and I've learned a lot from both Kyle and Mike. They're great coaches, and their teams are very competitive."
Although Belichick isn't coaching this season, he's clearly still in mid-season form with his press-conference-style answers—a fact he laughed about when it was pointed out to him.
Meanwhile, Shanahan does not doubt that Belichick's coaching days aren't over.
"I'm sure he's going to be back in the league next year, and I could be going against him," Shanahan said. "He could be in the NFC West. It would have sucked if he came here, and then he was going against us, so that's the stuff you have to be careful about. But he's the best, and I just like talking to him."