New England Patriots quarterback Tom Brady winds up to pass the ball during a training camp practice last month in Foxborough, Mass. (AP Photo/Steven Senne)

As Tom Brady prepares to play the upcoming season for the New England Patriots at age 42, the six-time Super Bowl-winning quarterback already is readying for the possibility — or perhaps the inevitability — of playing the 2020 season and beyond.

Brady has agreed to a two-year contract extension with the Patriots that runs through the 2021 season, according to people familiar with the situation. The new deal increases Brady’s 2019 income by about $8 million, to $23 million. It adds two additional seasons at prospective salaries of, according to the league-owned NFL Network, $30 million in 2020 and $32 million in 2021.

That makes the extension potentially worth $70 million, although adjustments are possible along the way as Brady and the Patriots operate on what amounts to a year-by-year basis.

“We’re all day-to-day if you think about it,” Brady said last week when asked about his contract during his meeting with reporters at the Patriots’ training camp. “None of us are really promised anything. I’m trying to do the best I can do today and just let those things sort themselves out.”

The Patriots had no immediate comment.

Brady’s deal had been set to expire following the 2019 season, after which he would have been eligible for unrestricted free agency. But Brady, agent Don Yee and the Patriots made certain it did not come to that.

Brady’s contract now runs through a season in which he will be 44. Continuing to play effectively as an NFL quarterback so far into his 40s would be unprecedented. But then, Brady already has amassed an unprecedented six Super Bowl triumphs after entering the league as an unheralded sixth-round draft choice in 2000.

The end of the Patriots’ dynasty clearly is in sight, with Brady turning 42 on Saturday and Coach Bill Belichick turning 67 earlier this year. But even after so much speculation in recent years that tensions among Brady, Belichick and owner Robert Kraft would lead to an imminent breakup, the group remains intact for now as the Patriots chase yet more on-field glory.

“I’ve had such a great experience over a lot of years,” Brady said last week. “I appreciate this team and the opportunity it gave me in 2000. I play for a great coach in Coach Belichick, and Josh [McDaniels, the Patriots’ offensive coordinator] and I have a great working relationship. I love Mr. Kraft and his family.

“We’ve had just incredible success. Hopefully we can keep it going.”

When he was asked last week whether he’d earned a new contract, Brady said: “I don’t know. That’s up for talk show debate. What do you guys think? Should we take a poll? Talk to Mr. Kraft. Come on. No, like I said, we’ve got a great relationship so we’ll see how it goes.”

The Brady of last season was not quite the league MVP version of the 2017 season. He threw for 4,355 yards with 29 touchdowns and 11 interceptions last season, compiling a passer rating of 97.7. But he and the Patriots returned to the top of the football world with their Super Bowl victory over the Los Angeles Rams in February in Atlanta.

This season, Brady must deal with the absence of tight end Rob Gronkowski, who announced his retirement in March. There has been speculation that Gronkowski might return at some point. But if he doesn’t, Brady will have to get by without the pass-catching tight end who has served as his security blanket.

“To replace great players, it’s not like you just pick another one off the tight end tree,” Brady said last week. “You can’t just go out back. You’ve got to find guys that come in and want to put the work in and want to try and contribute.”