Tom Brady will be taking a historic step in his football career.

The six-time Super Bowl champion quarterback and three-time NFL MVP announced Tuesday he will not return to the New England Patriots after a 20-year run with the franchise.

Brady did not reveal which team he would sign with or anything else about his plans beyond his intention to move on from the organization.

"To all my teammates, coaches, executives and staff, Coach (Bill) Belichick, RKK (owner Robert Kraft) and the Kraft family and the entire organization," Brady wrote on a post to his social media channels. "I want to say thank you for the past twenty years of my life and the daily commitment to winning and creating a winning culture built on great values. ... Although my football journey will take place elsewhere, I appreciate everything that we have achieved and am grateful for our incredible TEAM accomplishments."

Brady, 42, is set to become a free agent for the first time in his career on Wednesday, when the new league year officially begins. The Patriots will incur a $13.5 million dead salary cap charge by not re-signing him.

"I love Tom like a son and I always will," Kraft said in a statement. "He has brought so much happiness to me personally and to all of our fans. I had hoped this day would never come, but rather that Tom would end his remarkable career in a Patriots uniform after yet another Super Bowl championship. Unfortunately, the two sides were unable to reach an agreement to allow that dream to become a reality. While sad today, the overwhelming feeling I have is appreciation for his countless contributions to our team and community."

Said Belichick: ""Tom was not just a player who bought into our program. He was one of its original creators. Tom lived and perpetuated our culture. On a daily basis, he was a tone-setter and a bar raiser. He won championships in three of his first four years on the field and in three of his final six seasons with us, while competing for championships in most every season in between. This is a credit to Tom's consistency and what separates him. He didn't just perform. He didn't just win. He won championships over and over again."

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Brady's decision ends one of the most prolific pairings of team and player in sports history. A sixth-round pick out of Michigan in 2000, he rose from relative anonymity to become the most prominent football figure of his era and one of the greatest players of all time. His numerous records include most Super Bowl victories by a player (six), most Super Bowl MVPs (four), most Super Bowl touchdown passes (18), most Super Bowl passing yards (2,838) and most regular-season wins by a starting quarterback (219).

He also ranks second in career passing yards (74,571) and touchdowns (541), trailing only Drew Brees of the New Orleans Saints.

The 2019 season proved to be a challenging one for Brady. Following the retirement of tight end Rob Gronkowski, the Patriots' offense stalled at times, and the team went 4-4 after starting the year 8-0. Brady's 88.0 passer rating was his lowest since 2013.

Since making his earliest playoff exit in 10 years after the Patriots' wild-card round loss to the Tennessee Titans in January, Brady largely remained cryptic about whether he would actually leave New England. He stirred speculation on social media by posting a photo of him in a stadium, but the post was a teaser for his Super Bowl ad for Hulu.

“There’s a lot of speculation, a lot of people who don’t have any information,” Brady said on Westwood One radio in February. “I haven’t put too much thought into those things other than understanding the situation I am in, which I knew I was going to be in at the beginning of the year and just taking these things day-by-day. Again, the reality for me is the season didn’t end that long ago. There is still time to decompress a little bit and that will happen and continue to happen after the season. I will take those days as I need them and deal with the different emotions and ultimately when the time comes decide what’s next, that is what I will do.”

Brady's options in free agency are unclear, though the Tampa Bay Buccaneers and Los Angeles Chargers are among the notable teams that had been linked to him as possible destinations. Buccaneers GM Jason Licht acknowledged to ESPN that his team had spoken with Brady on Monday when the negotiating window opened, but he said there was no further talks Tuesday or deal in place.

"We're waiting to see what Tom decides just like everybody else," Licht told ESPN.

Several teams, however, already appear to be out of the running. The Tennessee Titans re-signed starter Ryan Tannehill to a four-year, $118 million deal on Sunday. The Las Vegas Raiders, meanwhile, reached a deal with former Titans quarterback Marcus Mariota, per reports, giving them a backup behind Derek Carr.

Follow Michael Middlehurst-Schwartz on Twitter @MikeMSchwartz.