In the final year of his contract, Tom Brady acknowledged the uncertainty of his future with the New England Patriots.

"I think that's the great part for me -- I don't know. I think that's been a unique situation that I've been in," Brady said Wednesday morning during his weekly Boston radio appearance.

"I think when you commit to a team for a certain amount of years, you kind of feel like your responsibility is to always fulfill the contract. For me, it's been good because I'm just taking it day by day and I'm enjoying what I have. I don't know what the future holds, and the great part is, for me, football at this point is all borrowed time.

"I never expected to play 20 years. I'm playing on a great team. It's just been an incredible 20 years of my life -- to play for Mr. Kraft, and Jonathan, and the Kraft family, and for Coach Belichick, and to have so much success is a dream come true."

Brady, who has previously said he hopes to play until he's 45, agreed to a revamped contract in August. The contract included voidable years in 2020 and 2021, which means he will become a free agent after the 2019 season unless the sides strike an extension.