Like seemingly every December for the past half-decade, rumblings have begun circulating this December about the Patriots and whether or not their dynasty is nearing the end. The speculation usually centers around quarterback Tom Brady and head coach Bill Belichick, the two men who both came to New England in 2000 and have been the centerpieces of the success New England has achieved over the past two decades. 

On Thursday night, during an interview with Karen Guregian of Boston, Brady's father, Tom Sr., weighed in on whether or not his son will be back with the Patriots in 2020. Brady, 42-years-old and nearing the end of his 20th regular season in New England, is currently signed through the 2021 season. And while he's helped lead the Patriots to a 10-2 start, injuries to his receiving corps have led to underwhelming production from Brady as of late, as he is completing 61.1% of his passes, his lowest mark since the 2013 season. 

"You know, I don't know. It's hard for me to envision him playing somewhere else. He wants to play. But ultimately, it's Bill's decision," said Brady Sr., who has openly speculated about how his son's time in New England will end before. "Nobody really knows. Bill doesn't tip his hand. There's just been insinuations here and there. This is really kind of between those two. They got to decide what they want.

"If Bill says he doesn't want Tommy, and Tommy wants to play, well, Joe Montana went to Kansas City … just because Bill decides he wants to move on, that won't dictate Tommy's future. I'm sure there are a few other teams in the league that would want him."

Brady Sr. added that his thoughts are pure speculation. 

"I just know 20 years in the league, Bill doesn't keep old guys very long," he said. "If that's what Bill wants to do, Bill doesn't keep the contract. Who knows? Tommy is an anomaly in this equation. Given he's been here 20 years, no one has been here like that. Everybody has a conclusion to their career that's generally not in their hands."

The Brady-Belichick relationship has been analyzed and scrutinized on various occasions over the past several years and was a major topic in Ian O'Conner's 2018 biography on Belichick. In the book, O'Conner states that Belichick -- with Spygate already a blemish on his resume -- tried to distance himself from the "Deflategate" saga that consumed parts of three seasons in New England. O'Connor wrote that Brady was hoping for more public support during that time from Belichick, who in 2017 was reportedly forced to trade quarterback Jimmy Garoppolo after losing a power struggle with Patriots owner Robert Kraft. 

The outside noise during that time grew to such a level that Patriots issued a joint statement during the 2017 playoffs on the relationship between Kraft, Belichick, and Brady. New England ended up winning their third AFC title in four years that postseason before losing to the Eagles in Super Bowl LII. New England rebounded to win their third Super Bowl in four years in 2018 while joining the 1990s Bills and 1970s Dolphins as the only teams to appear in three consecutive Super Bowls. The Patriots, with six Super Bowls wins during the Brady-Belichick-Kraft era, are trying to help the Patriots become the first franchise to win seven Vince Lombardi Trophies. 

Brady and Belichick have both recently praised the other in public settings. Belichick lauded Brady's performance shortly after the Patriots defeated the Rams in this past year's Super Bowl. Brady, the only four-time Super Bowl MVP, recently called Belichick the "greatest coach of all-time." 

While they clearly have respect for one another, and what they've been able to accomplish together, everyone has an ego, including Belichick, who earlier this year became the third coach in NFL history to win 300 games. In his book, O'Connor wrote that Belichick has confided some close to him about his dismay on the possibility of never getting to coach without Brady as his quarterback. If true, Belichick's drive to prove that he can win a Super Bowl without Brady could be what ultimately ends the most successful coach-quarterback duo in NFL history.