Postpublished at 20:50 Greenwich Mean Time 9 January 2021
Is that Manchester United midfielder Fred? He shouldn't be watching TV on the bench!
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Stevenage are 22nd in League Two
Swansea are second in the Championship
The Welsh side have twice been semi-finalists - last in 1964
Emma Sanders
Is that Manchester United midfielder Fred? He shouldn't be watching TV on the bench!
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I actually turned over from Celebrity Antiques Road trip to watch this match.
Fred, Manchester
Man Utd 1-0 Watford
Chris Waddle
Ex-Tottenham and England winger on BBC Radio 5 Live
Watford have improved, but I think Man United have become more sloppy than anything, giving Watford confidence.
It is encouraging Watford, and has them thinking 'this is not as hard as I thought it would be'.
Man Utd 1-0 Watford
In the meantime, Watford continue to attack. Nathaniel Chalobah's strike from the edge of the box is blocked by Scott McTominay.
And here comes Harry Maguire, who is going to replace Eric Bailly.
Man Utd 1-0 Watford
Eric Bailly looks a bit groggy. He's being helped off the pitch by the medical staff, who are asking him questions and holding his neck, which looks to be the problem.
It doesn't look like United have a substitute ready so seems they're happy for him to carry on. Ole Gunnar Solksjaer is getting the low down from his medical team.
FT: Wycombe Wanderers 4-1 Preston North End
Eric Bailly is still being checked over by the medical staff so worth having a watch of the highlights from Wycombe's comfortable win over Preston North End earlier.
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Harrison: Bailly is a great tackler and reads the game well, but his distribution needs a lot of work before he can realistically cement a starting XI spot.
Man Utd 1-0 Watford
Ismaila Sarr is caught on the ankle by Jesse Lingard and he wins a free-kick for Watford over on the right.
Doesn't beat the first man but Alex Telles' clearance is poor. It comes back in and Dean Henderson flaps at it, taking out Eric Bailly and William Troost-Ekong in the process.
It's eventually headed behind for a goal kick but Bailly is getting some treatment.
Man Utd 1-0 Watford
Chris Waddle
Ex-Tottenham and England winger on BBC Radio 5 Live
For the first 10 or 15 minutes I thought 'how many are Man United going to score here tonight?'
But since that opening 15 minutes they have been very disappointing on the ball, selecting options on the ball, giving it away all the time and cheaply.
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Have United gone home? This is woeful.....
Stevo, Manchester
Man Utd 1-0 Watford
Much better from United. Mason Greenwood touches it on to Donny van de Beek. He backheels it into the path of Juan Mata in the box but he's denied by the legs of goalkeeper Daniel Bachmann.
Man Utd 1-0 Watford
Tom Gayle
BBC TV at Old Trafford
Xisco Munoz and his assistant Roberto Cuesta are an energetic duo.
Neither has sat down all game. Constantly barking instructions mixing between English and Spanish.
It’s fair to say their encouraged by what they’ve seen from Watford.
FT: Blackpool 2-2 (3-2 pens) West Brom
Big win for Neil Critchley's Blackpool earlier. They saw off West Brom in a penalty shootout.
Man Utd 1-0 Watford
The corner is again cleared but only to the edge of the box. This time, Daniel James anticipates it and gets there first.
Will Hughes completely takes him out in the process though.
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Daniel: Watched the QPR v Fulham west London derby snore fest, only bought to life in ET. A full, noisy Loftus Road, would have sparked some life into this match.
John: The FA Cup will always be the fans' favourite but empty stadiums, nail biters, happy faces, sad faces, jubilation and hugging are just a few of the things we all really miss.
Man Utd 1-0 Watford
Simon Stone
BBC Sport at Old Trafford
Manchester United have lost their way.
They started well but the longer the half has wore on, the more disjointed they have become.
I would be expecting Juan Mata to exert more control over the game. Instead, Watford are the ones growing into it.
Man Utd 1-0 Watford
Ismaila Sarr tries to get the ball back off Jesse Lingard as United break through the middle but he brings him down with a tug of the shirt. Into the book...
Watford then come away down the right through Sarr and Alex Telles has to concede a corner.
Man Utd 1-0 Watford
William Troost-Ekong gets there ahead of Eric Bailly on the corner but it's just too high and he flicks it wide.
Probably mistimed his jump a little too.
FT: Huddersfield 2-3 Plymouth
Five goals at John Smith Stadium earlier!
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Why on earth has Ole told James , Greenwood and Mata to rotate positions, when we only have Greenwood playing who can actually strike the ball? The guy is clueless.
Jason, Devon