Are you old enough to remember the Sheffield Wednesday - United derby of 1979?
A crowd of no fewer than 49,309 were at Hillsborough on Boxing day in that year - and that figure became a record for the Football League's old Third Division.
It wasn't a day to cherish for the Blades fans - they lost 4-0.
The next Sheffield derby didn't take place until 1991 and United were 2-0 winners.
Here are some other sporting events which happened on Boxing Day in years gone by:
1908: Texan Jack Johnson became the world's first black heavyweight boxing champion. He was not allowed to fight in his native America because of racial prejudice, but travelled to Sydney where he beat Canadian Tommy Burns when the referee stopped the fight in the 14th round.
1935: Tranmere beat Oldham 13-4 at Prenton Park - a record Football League scoreline. Centre-forward Bunny Bell also went into the record books by scoring nine of Tranmere's goals, but that mark lasted only four months before Luton's Joe Payne scored 10 against Bristol Rovers.
1970: Lillian Board died of cancer, aged only 22. Board had been a 400 metres silver medallist at the 1968 Olympics and won the 800m European title in Athens the following year.
2006: Australian leg-spinner Shane Warne became the first bowler in Test history to claim 700 wickets when he dismissed England's Andrew Strauss in Melbourne.
2012: Nottingham Forest parted company with manager Sean O'Driscoll just hours after a 4-2 home win over Leeds left the club one point adrift of the Championship play-off places.
2013: Kevin Pietersen went past Geoffrey Boycott into fourth place among England's top all-time Test run-scorers during a doughty 67 not out in the fourth Ashes Test in Melbourne.