Michael Emons
BBC Sport at Old Trafford

The West Ham fans, as they have been since before the game started, are in great voice. And their team should be ahead.

They had the best chance of the opening half hour when Said Benrahma's delicious through ball evaded both Victor Lindelof and Harry Maguire, who made a mess of an attempt to play offside.

That left Michail Antonio to run through on goal, but the finish lacked conviction and David de Gea kept it out, with Tomas Soucek heading into the side netting from the following corner.

Benrahma has been at the heart of the Hammers' best moves and also set up Lucas Paqueta but the Brazilian could only shoot at De Gea.

Fleetwood's players are still arguing with officials on the pitch. They can't believe Cian Hayes was shown a straight red.

And that ends the half. Fleetwood are still in it but they're down to 10 men.

Nooo, the worst possible thing for Cian Hayes on the stroke of half-time as his foot is high in a challenge and he's shown a straight red. He can't believe it!

Martin Keown
Former England defender on BBC One

Tottenham can't break free of this Sheffield United defence.

Clinton Morrison
Former Republic of Ireland striker on BBC Radio 5 Live

You can see that Tottenham are getting frustrated. It's all too comfortable for Sheffield United. It's probably a game plan for them. They'll wait until 30 minutes to go and then start using their top players from the bench and try and nick the game.

Pat Nevin
Former Scotland winger on BBC Radio 5 Sports Extra

Manchester United are missing Casemiro, he is the real controlling element in the midfield for them there. Scott McTominay is a good player but United just don't look as controlled.

Knocking on the door of half-time and Burnley have been hugely frustrated. Fleetwood have carried a small threat on the break but haven't had many opportunities.

Burnley's Jordan Beyer blatantly handballs a cross but Fleetwood can't take advantage of the set-piece.

Twenty minutes on the clock. This is what you call a slow burner. Yet to burst into life.

babyboomer: Lack of cohesion up front for Man United. Weghorst is a yard or 2 short of pace, Antony a passenger again & Garnacho needs the ball playing in clear space ahead of him or he just get crowded out.

West Ham are starting to open Man Utd up. Lucas Paqueta is teed up in the centre but he's a long way out. He hits it first time but it's straight at David de Gea.

Harry Maguire chops down Michail Antonio and he's in the book.

Cian Hayes wins a free-kick deep in the Burnley half. Fleetwood have a chance to test Bailey Peacock-Farrell...

It doesn't beat the first man.

Chris Wise
BBC Radio 5 Live commentator at St Mary's

Really Southampton have not prised Grimsby open and there was some discontented voices from the home fans as the half-time whistle was blown.

Quiet start at Bramall Lane but Wes Foderingham is forced into a save by Son Heung-min who tries to curl one from the edge of the box.

From the corner, Tomas Soucek heads it just wide, into the side-netting. Close...

HUGE chance. David Moyes is flapping his arms. Michail Antonio is clean through, runs half the length of the pitch but can't beat David de Gea, who stands his ground to pull off a crucial save.

This is what the FA Cup is all about. Brilliant scenes in the away end. Four thousand Grimsby fans - many holding inflatable haddocks - are punching the air as the teams head for the dressing rooms.

League Two Grimsby are 45 minutes away from a huge shock.

Image source, Getty Images

Bruno Fernandes picks up a risky pass from Pablo Fornals. He slides in Antony but he can't beat Ben Johnson in the box. Decent defending!

Ian Dennis
BBC Radio 5 Live senior football reporter

Starting to see a lot more of Tottenham on the ball after a very quiet five minutes at the start from the away side.