Quarterback Tom Brady has announced he is leaving the New England Patriots after a 20-year spell with the team, which has seen him win six Super Bowls.
Brady, 42, was drafted by the Patriots in 2000 and helped them win the Super Bowl in 2001, 2003, 2004, 2014, 2016 and, at the age of 41, in 2019.
He has also been on the losing team in the Super Bowl on three occasions.
"Pats Nation will always be a part of me, I don't know what my football future holds," said Brady.
"It is time for me to open a new stage for my life and career.
"Although my football career will take place elsewhere, I appreciate everything we have achieved and am grateful for our team accomplishments."
Brady is a free agent this off-season and was able to speak to rival teams from Monday with the full free agency window opening on Wednesday.
In a statement posted on social media, Brady added: "I wanted to say thank you to all of the incredible fans and Patriots supporters.
"MA [Massachusetts] has been my home for 20 years, it has truly been the happiest two decades I could've envisioned in my life and I have nothing but love and gratitude for my time in New England.
"The support has been overwhelming, I wish every player could experience it."
'The greatest quarterback of all time'
New England Patriots head coach Bill Belichick, who has been at the team throughout Brady's career, said: "Tom was not just a player who bought into our program, he was one of it's original creators - he lived and perpetuated our culture and on a daily basis he was a tone setter and a bar raiser.
"He didn't just perform, he didn't just win, he won championships over and over again.
"Tom and I will always have a great relationship built on love, admiration, respect and appreciation and his success as a player and his character as a person are exceptional. It has been a privilege to coach Tom Brady for 20 years.
"Sometimes in life, it takes some time to pass before truly appreciating something or someone but that has not been the case with Tom. He is a special person and the greatest quarterback of all time."
'I had hoped this day would never come'
Patriots chairman Robert Kraft also released a statement and said: "I love Tom like a son and I always will. He has brought so much happiness to me personally and to all our fans.
"I had hoped this day would never come, but rather 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. He has been an exemplary team-mate and leader - there simply will never be another Tom Brady."
Where could Brady go?
One place Brady will not be going is New Orleans. Drew Brees, the only man with more all-time passing yards and touchdown passes than Brady, has confirmed he will stay with the Saints, whose back-up quarterback Teddy Bridgwater is now a free agent.
But the Los Angeles Chargers need a new QB with veteran Philip Rivers leaving, while Tampa Bay Buccaneers coach Bruce Arians has named Brady as a potential target after Jameis Winston became the first man to go 30 for 30 - throwing 30 touchdown passes and 30 interceptions in the same season.
The Raiders are relocating from Oakland to Vegas and may consider trading Derek Carr in favour of a big name to help fill their new 65,000-seater stadium and create a buzz around Sin City.
Tennessee was touted as a possible destination until Ryan Tannehill, who took the Titans to within one game of the Super Bowl after becoming the starter mid-season, signed an extension on Sunday.
Who would replace Brady?
Rivers and Winston are both free agents, and Andy Dalton could be made available too. The Cincinnati Bengals have this year's first draft pick and are expected to choose highly-rated QB Joe Burrow, allowing Dalton to move on.
Surprisingly, the San Francisco 49ers, who were less than three minutes from winning Super Bowl 54, have emerged as a potential suitor for Brady. It's been rumoured that Brady's boyhood club are interested in bringing him home to California and trading his former back-up Jimmy Garoppolo back to the Patriots.
And the likes of Cam Newton, Joe Flacco and Nick Foles, who have all led teams to the Super Bowl in the last seven years, may also be given the chance to start afresh after poor form and injuries. The speculation is just getting started.