ALLEN PARK, Mich. -- One day after finalizing a new contract that increases his pay by $8 million this season, New England Patriots quarterback Tom Brady acknowledged how the deal doesn't tie him to the franchise beyond the 2019 season.

"It's a unique situation I'm in -- 20th year with the same team, I'll be 42 years old. So pretty much uncharted territory for everybody," Brady said Monday after a joint practice between the Patriots and Lions. "I'm going to go out there and do the best I can this year and see what happens."

Brady's new contract is technically a two-year extension through the 2021 season, but 2020 and 2021 are void years, a source told ESPN's Field Yates. That is similar to the Saints' five-year extension with quarterback Drew Brees in 2016 that included three void years, which essentially made it a two-year deal.

Teams use void years for salary-cap purposes, although this is the first time the Patriots have ever done so.

So Brady and the Patriots will have to revisit negotiations before the end of the 2019 league year to extend the contract, and it is expected they will do so. The Patriots have agreed not to use the franchise tag on Brady, according to a source.

"It's really the reality for most guys in the NFL. I don't want anyone to think I'm any different from everyone else. Football is 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," Brady said.

"I've just had a great history here. I love playing quarterback here. I love this team, this organization, Mr. (Robert) Kraft, Jonathan (Kraft), Coach (Bill) Belichick, all the coaches, all the players. The focus is this year and what we have to do. That's where I'm focused. That's all that really matters in the end, and that's what this team expects of me -- to put everything into it, like I always have. I'm really excited for the year."

Asked if he was relieved to have his contract status clarified, Brady turned to one of Belichick's catchphrases.

"It is what it is. That's a good line. Whoever said it; it's very pertinent. Like I said, there are a lot of guys who have one year left on their contract. So the situation -- I have one year to go, we'll see what happens."