There's a roar from the away end as Jacob Mendy charges down the flank but sees his run halted on the edge of the box. Sheffield United then break quickly but their attack is also snubbed out.

High tempo start to this game.

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

Wrexham's main focus is to get promoted out of the National League but it is still a great opportunity to cause an upset.

You've just got to manage the game, you can't come out all guns blazing because Sheffield United have picked a strong team.

Will we get to see any upsets tonight? Tonight's FA Cup action is getting under way.

Remember there is extra time and penalties in tonight's replays if they are needed.

Matt Upson
Former Arsenal defender on BBC Radio 5 Live

Wrexham has big links to the FA Cup because of that moment many years ago. Also, it has a big following and it has been suffering as a club.

The resurgence of it, the fresh injection, the fresh outlook which is very different, it might not be for everyone but they're certainly getting involved and it's something to cheer about.

At the moment, a cup run for Wrexham and where the club are going, it's important in the area for the community. It runs deeper than football and you see that in their away turn out this season which is really strong.

Image source, .

Promotion is clearly the priority for Sheffield Wednesday. They have been on a great run to go top of League One, but they still have to watch out for teams like Derby who are giving it a real go to catch them.

Fleetwood got a really good draw at Hillsborough first time out, and you might think home advantage gives them the edge now, but I actually think Wednesday will nick this one.

Sutton's prediction: 0-1

Wrexham have scored 14 goals in the FA Cup since the first round, the most by a non-league side in a single campaign since Woking in 1978-79, when they also scored 14.

Watch the best goals from the FA Cup fourth round, which featured fine strikes from the likes of Nathan Ake, Casemiro and Son Heung-min.

Matt Upson
Former Arsenal defender on BBC Radio 5 Live

It could get better for Wrexham. Whether or not it's luck or whether it's a team on the crest of a wave. I think we'll see tonight.

They are going to a place that is notoriously difficult to play at when it's an FA Cup game.

It's an evening under the lights at Bramall Lane, it's special. it really is.

Every time I have been there to watch Sheffield United, whether in the Premier League or any division or to play at, it's one of those stadiums that lends itself brilliantly to these occasions with the way the fans view it and they whip up the atmosphere.

Massive test for Wrexham but they are in a good place and they have got plenty of confidence at the moment.

Image source, .

I sensed some unhappiness from Ipswich supporters towards me after I went for Burnley to win 4-0 at Portman Road, and the game finished 0-0.

But both teams made so many changes when they first met that it made it incredibly difficult to predict what would happen.

I can definitely see Ipswich manager Kieran McKenna doing the same again on Tuesday, and why wouldn't he?

It's a long way for them to travel to Turf Moor and they play League One leaders Sheffield Wednesday on Saturday.

On top of that, Burnley's home record this season is almost impeccable, with 11 wins and four draws from 15 games in the Championship.

It's going to be a long journey home for Ipswich fans, and I think it is going to be a miserable one.

Sutton's prediction: 5-0

Pretty sure it is written in law that all live text commentaries of FA Cup games must feature a photo of a tin foil FA Cup.

So here we are...

Image source, Getty Images

Manager Phil Parkinson does not believe Wrexham's hopes of causing an FA Cup fourth-round upset against Sheffield United are over.

"We'll be going there to make it a cup tie and give everything that we've got to try and get through," Parkinson said.

"Logic tells you that our great opportunity was to win the game at home but equally we went to Coventry and played really well on the day."

Well Chris Sutton is being a bit of a spoilsport so far, predicting zero upsets.

Surely we will get at least one surprise result tonight?

Image source, .

This one surprised me, with Grimsby getting a 2-2 draw at Kenilworth Road a few days after being smashed 5-0 by Swindon in League Two.

Luton's level of performance was awful for a team in the Championship play-offs, and Grimsby might even have won it first time around - so they will certainly fancy their chances on their own patch.

I don't see Luton being as bad again, though. Maybe Grimsby's chance has come and gone?

Sutton's Prediction: 0-2

Prior to the first game against Sheffield United, Wrexham co-owner Ryan Reynolds spoke about the club and how things have been since he and and Rob McElhenney took over in November 2020.

The FA Cup fourth-round replay between Sheffield United and Wrexham is on BBC Radio 5 live tonight.

Meanwhile, commentary on Grimsby versus Luton is on 5 live sports extra.

Image source, .

This is another tie where it feels like the underdogs have had their chance.

Wrexham had their opportunity, when they were at home and in front against Sheffield United's 10 men deep in stoppage time.

It was all there for them but they could not manage the Hollywood finish to hold on and set up a fifth-round tie with Tottenham.

Everyone is talking about how exciting that game would be for the Welsh side but they are wrong to ignore Sheffield United after their form this season.

Even if the Blades make more changes, they should win at home and make plans for when Spurs are in town in a couple of weeks.

Sutton's Prediction: 5-1

Matt Upson
Former Arsenal defender on BBC Radio 5 Live

I'd like not to think that Wrexham have made the changes because of their league form and what they are chasing in terms of promotion.

Obviously that is a huge objective in terms of the club, they are in that position where you have to decide what is more important or you can cover both bases.

Whether or not those changes will suit the approach in terms of being harder to break down, slightly more defensive, we'll have to wait and see.

The key player, Mullins, in terms of goals. Seven goals in four FA Cup games this season which is incredible, he is an out and out poacher and somebody who comes alive in the box.

When you defend well and you have a player like that in your team, you can always win football matches and perhaps that's what they're banking on this season.

Need a reminder of how the original fixtures unfolded for each of tonight's replays?

Watch the highlights below.