The Sun on Sunday clip claims to show the England captain collapsed on the floor after Bardsley delivered a blow to his face in what appears to have started as a play session between two friends.
Onlookers can be heard laughing after Rooney falls down prostrate and the video abruptly ends.
The Sun claims the footage was shot at Rooney’s home on 22 February - the day after Manchester United's 2-1 defeat to Swansea.
Rooney is due to lead United out at Old Trafford this afternoon for their Barclays Premier League match against Tottenham.
The club refused to comment on the video when contacted this morning and Rooney's representative did not return calls.
Rooney has spoken of his love for boxing in the past. The 29-year-old is friends with Manchester fighter Anthony Crolla and super-middleweight fighter Paul Smith from Liverpool.
He once also carried Ricky Hatton's belt into the ring prior to his fight against Jose Luis Castillo in Las Vegas eight years ago.
Rooney started boxing when he was in the youth team at Everton and revealed last November he would have considered taking the sport up professionally if he had not made it as a footballer.
In 2008, Rooney said: “I've always loved watching boxing and I went boxing training for about three or four years when I was younger. It's a sport I've always been involved in.
"I was doing both boxing and football training at one stage when I was about 15. But Everton who I was with at the time, said I had to concentrate on one of them and I opted for football."
With additional reporting from the Press Association.
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