ALLEN PARK, Mich. — After being treated to a post-practice rendition of “Happy Birthday” by his New England Patriots teammates, Tom Brady stepped to the podium to discuss the belated birthday gift he received from the team: a two-year, $70 million contract extension.

“We’ve just had a great history, and you know I love playing quarterback here,” the Patriots quarterback said following the Patriots’ first joint practice with the Detroit Lions. “I love this team, the organization, Mr. (Robert) Kraft, Jonathan (Kraft), Coach (Bill) Belichick, all the coaches, all the players.

“I mean, the focus is this year and what we’ve got to, so that’s where I’m focused. That’s all that really matters in the end, and that’s what this team expects from me — to put everything into it like I always have. I’m really excited for the year. This was good competition today.”

Brady’s extension reportedly will pay him an additional $8 million this season, but it came with an important caveat: the next two years of the deal are voidable, meaning the sides almost certainly will need to renegotiate again before the 2020 campaign begins. (UPDATE: The terms of the deal actually will make Brady a free agent after the 2019 league year concludes, according to a report from NFL Media’s Ian Rapoport.)

That means Brady, who turned 42 on Saturday, essentially will be on a series of one-year contracts for the remainder of his Patriots tenure. Though he’s long expressed a desire to play until he’s 45 — and rarely agrees to discuss contract-related matters — the surefire Hall of Famer acknowledged he’s entering “uncharted territory” and said he understands the benefits of this contract structure.

“I mean, it’s really the reality for most guys in the NFL,” Brady said. “I don’t want to think that I’m any different than everyone else. Football’s a tough business. It’s a production business. I’m ready to go this year, and that’s really what matters, and that’s where my focus is.

“It’s a unique situation I’m in. I’m in my 20th year with the same team, and (I’m) 42 years so, so pretty much uncharted territory for everybody. I’m going to go out there and do the best I can this year and see what happens.”

Asked if he would have preferred a contract with more security, Brady replied: “I’m really not worried about it.”

“I’m secure for this year — I think,” he joked. “At least I get a few first-team reps out there. So I’ll just go out there and do the best I can.”

Later, when Brady was asked whether he was relieved to get this extension signed before the season began, he paused, grinned and then channeled his head coach.

“It is what it is,” he said. “That’s a good line. Whoever said it, it’s very pertinent. Like I said, there’s a lot of guys who have one year left on their contracts, so it’s a situation (where) I have one year to go, and we’ll see what happens.”

Belichick himself briefly addressed Brady’s extension during his pre-practice news conference.

“On the Brady contract, you know it’s always good to come to an agreement with a player — any player — so that’s a good thing,” the coach said. “I’m not going to talk about the contract, so we’ll move on from that and focus on what we’re here for, which is a great opportunity to work against the Lions.”

Thumbnail photo via Greg M. Cooper/USA TODAY Sports Images