Tom Brady's retirement from the NFL lasted 40 days.

Brady revealed on Sunday he's returning to the Tampa Bay Buccaneers for his 23rd NFL season.

The seven-time Super Bowl champion announced his decision on Twitter and Instagram, saying he has "unfinished business".

"These past two months I've realised my place is still on the field and not in the stands," Brady wrote.

"That time will come. But it's not now. I love my teammates, and I love my supportive family. They make it all possible. I'm coming back for my 23rd season in Tampa."

Brady led the Buccaneers to a Super Bowl title after the 2020 season and NFC South championship last season.

He teamed with coach Bill Belichick to win six Super Bowls during 20 seasons with the New England Patriots.

The 44-year-old Brady led the NFL in yards passing (5,316), touchdowns (43), completions (485) and attempts (719) in 2021, but the Buccaneers lost at home to the Los Angeles Rams in the divisional round.

Brady cited his desire to spend more time with his wife, supermodel Gisele Bundchen, and three children when he decided to walk away from the game on February 1.

His decision came a day after attending Manchester United's 3-2 Premier League win over Tottenham Hotspur.

Perhaps Brady was inspired to make a comeback after watching another sporting great, Cristiano Ronaldo, score a hat-trick to lead his side to victory at Old Trafford.

Brady sat with the Glazer Family, who own both United and the Buccaneers.

His reversal sent shock waves throughout the sports world, and his teammates and Buccaneers fans reacted with jubilation.

"He's baaackkkk," declared the Bucs on Twitter, with a video of the quarterback taking the field.

All-Pro right tackle Tristan Wirfs called it "unreal". Receivers Mike Evans and Chris Godwin shared their joy in emojis.

Many Hall of Fame players across several sports returned to playing after retiring, including Michael Jordan and Magic Johnson in the NBA, Brett Favre and Reggie White in the NFL, Guy Lafleur and Mario Lemieux in the NHL.

The Buccaneers are hopeful star tight end Rob Gronkowski also returns, with Brady having convinced his friend to reverse his retirement to join him in Tampa in 2020.

Brady is the NFL's career leader in yards passing (84,520) and TDs (624). He's the only player to win more than five Super Bowls and has been MVP of the game five times.

Brady has won three NFL MVP awards, been a first-team All-Pro three times and selected to the Pro Bowl 15 times. He is 243-73 in his career in the regular season and 35-12 in the playoffs.