Robbie Savage and Alan Shearer have kicked-off a 57-hour five-a-side game for Sport Relief.
The match, between BBC 5 live and Match of the Day, outside BBC MediaCityUK in Salford started at 09:15 GMT and ends on Saturday at 18:15.
About 1,000 people will play 30 minutes alongside pundits Savage and Shearer.
All-time Premier League top goalscorer Shearer is captaining the Match of the Day team while ex-Wales player Savage leads the radio outfit.
The 57-hour duration of the epic encounter has been chosen since it is the equivalent of a Premier League club's entire season.
Two years ago, Shearer and Savage raced against each other at Wembley Stadium to see who could be the first to sit on 45,000 seats.
Former Blackburn and Newcastle striker Shearer won that race, raising hundreds of thousands of pounds in the process.
He said he was "feeling confident" of securing bragging rights again, albeit with the help from hundreds of others.
"We're not as young as we were when we faced each other on the pitch in the Premiership," he said, adding: "So it'll be great to have the help of the playing fans."
Savage said he "can't wait to take on Shearer" alongside players gathering in Salford from across the UK.
"Most importantly we are raising money for a great cause," he added. "Even if we can't stand at the end of the three days, it will be worth it."
The professionals will each take part for at least 12 hours with Shearer putting in a 09:15-21:15 stint on Thursday and Savage the same times on Friday.
Since 2002, Sport Relief has raised more than £262m for disadvantaged people in the UK and overseas.
Shearer v Savage:
Teams: Southampton (1988-92), Blackburn (1992-96), Newcastle (1996-2006)
Premier League appearances: 441
Premier League goals: 260 (all time-record scorer - Wayne Rooney is second, on 192)
Honours: Premier League winner (1994-95)
England caps: 63
England goals: 30
Played in the 1996 and 2000 European Championships and the 1998 World Cup
Teams: Manchester United (1993-94), Crewe Alexandra (1994-97), Leicester City (1997-2002), Birmingham City (2002-05), Blackburn Rovers (2005-08), Derby County (2008-2011), Brighton & Hove Albion (loan in 2008)
League appearances: 537
League goals: 37
Honours: League Cup winner (1999-2000)
Wales caps: 39
Wales goals: 2