Andrew: Ordinarily, you wouldn't give Brighton a chance at Old Trafford, but I can't help feeling the weather might have a part to play here.

Dave: United's passing is not good enough. They have to pass to a stationary target - the accuracy & weight of pass is not good enough to find men running into space.

Jose Mourinho is urging his players forward. Anthony Martial tries to link up with Juan Mata but the attack stalls.

But United are just gifted a corner as Davy Propper slices a clearance horrendously.

Image source, Getty Images

At the other end, Ezequiel Schelotto has a shot. He opts for an effort along the ground, which in these conditions may not be the best bet.

The ball leaves a trail through the snow, and looks to have slowed up as it goes harmlessly wide. Might be a day for getting the crosses in, going direct and looking for the head of the front man instead of shooting along the ground.

Simon Stone
BBC Sport at Old Trafford

It is very cold here tonight. Hardly anyone in the press box is not either wearing a hat or has their hood pulled up.

So, credit to Antonio Valencia, Eric Bailly, Scott McTominay and Juan Mata from Manchester United and Lewis Dunk and Shane Duffy from Brighton, who are all wearing short sleeved shirts and no gloves.

Image source, Reuters

When United have the ball, Brighton seem to have a back six. Whatever it takes, will be the message from Chris Hughton.

Jesse Lingard, after a decent spell of Manchester United possession, tries his luck. But it is well wide.

Image source, Reuters

And breathe, George...

A first sighting of the Brighton goal from Romelu Lukaku. United captain Antonio Valencia fizzes a waist-high cross into the near post from the right, but Lukaku, surrounded by two Brighton defenders, can only divert in well wide of Tim Krul's goal.

Brighton defenders just about did enough on that occasion.

Image source, re

This is the first FA Cup meeting between the sides in more than 25 years. Ryan Giggs' goal was the difference back in 1993.

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Stephen Warnock
Ex-Liverpool defender on BBC Radio 5 Live

Image source, Rex Features

It is a big night for Luke Shaw. If you look at that England squad and people in front of him there is some work to do.

He is a player who hasn't shown his full potential at United, tonight is a chance to show Jose Mourinho what he can do.

Anthony Martial is again looking lively down the United left flank. Nemanja Matic gets the ball off of Juan Mata and he is sends in a cross. It is a bit nervy from Brighton keeper Tim Krul, who drops it but gathers it at the second attempt.

We'll put that one down to the slippery ball and the slippery surface. Get the crosses in when you can on that evidence.

Stephen Warnock
Ex-Liverpool defender on BBC Radio 5 Live

I'm disappointed in the team Manchester United put out. After going out of Europe, as a fan you want a day out at Wembley, to say you have won something. I still think managers don't give the FA Cup enough respect.

Image source, Reuters

Simon Stone
BBC Sport at Old Trafford

Image source, PA

The match has kicked off in heavy snow - we are in March aren't we?

It has also started to a lot of noise from the singing section, which has been installed by United for this game in the area normally reserved for the away fans, who have been moved to a different area.

Lots of songs are being sung. Let's see how long it lasts.

David freedman: Playing in snow like this makes no sense.

Image source, Reuters

Anthony Martial is the first Manchester United player to try to make an impact. He jinks in from the left wing across goal, shoots from 25 yards out but it deflects off Solly March and the corner from the right-wing comes to nothing.

A decent start for the visitors. Jurgen Locadia is in a promising position on the edge of the box, but the chance is snuffled out and the ball played in the box is easily cleared.

Manchester United get us under way. We start off with the white ball. With the snow coming down, and coming down quickly the rarely-seen orange ball could be making an appearance later on.

Image source, Reuters

The snow is going to cause some havoc tonight. It is already settling on the pitch. Perfect conditions for an upset? We will see.

Image source, Reuters

Head-to-head

• Manchester United and Brighton have not met in the FA Cup since January 1993, with United winning 1-0 with a goal from Ryan Giggs.
• The Seagulls have only won one of their 17 matches against United in their history (drawn five, lost 11), winning 1-0 in a top-flight fixture in November 1982.

Manchester United

• United have been eliminated from three of their past four FA Cup quarter-finals, progressing only in 2015-16 against West Ham after a replay.
• Romelu Lukaku has scored 11 goals in his past 10 FA Cup appearances.
• Mourinho has won 14 of his 16 home FA Cup matches (drawn one, lost one), winning all three with United by an aggregate score of 10-0.

Brighton

• This is only Brighton's third FA Cup quarter-final appearance and their first since 1985-86.
• Hughton has managed four matches at Old Trafford in all competitions and lost all four without seeing his sides score a goal.
• Brighton have lost seven and drawn one of their past eight away FA Cup matches against top-flight opposition.

Former Manchester United first-team coach Rene Meulensteen speaking on Sportsworld BBC World Service said: "The DNA of Manchester United under Sir Alex Fergusson was attack and to play attractive football and yes it was sometimes cavalier. Number one under Sir Alex was to win and number two was to entertain the crowd.

"We wanted to win the best possible way. It was not always possible but that was the intention. Mourinho is more pragmatic we saw it in the Chelsea game at home in the first half and in the second half against Liverpool. That is what frustrates the fans the most.

“They have to make a clear statement tonight come out and be positive and take the game to Brighton. The whole season falls to tatters if they don’t win tonight “