And here's a shot of Billy Sharp restoring United's lead.

Image source, Rex Features

Finally there's a bit of calm at the Pirelli Stadium as we approach half-time.

There's a break in play as Leon Clarke stays down after being fouled by Burton defender Stephen Warnock.

It's difficult to say where this match stands now, but the Blades look very dangerous every time they pile foward.

Lilywhites keeper Chris Maxwell is called into action by Bolton again, this time as Adam Armstrong shoots straight at him from a narrow angle.

There's seven minutes left until the break at Deepdale.

Just as I say that, the Blades almost extend their lead.

Leon Clarke, who scored four against Hull last time out, hits a curling effort first-time which strikes the Burton post.

All of a sudden this one is too hot to handle!

Bolton have their first proper effort at goal, as a miscued clearance falls to Josh Vela, who sends the ball narrowly over the bar on the half-volley.

Preston keeper Chris Maxwell actually got fingertips to that one.

Image source, Rex Features

It's fair to say this man, and his opposite number Nigel Clough, have gone through all the emotions in the past five minutes.

But thanks to Billy Sharp, Sheffield United will end the evening top of the Championship again... as things stand.

Chris Wilder knows that could all change so easily, though.

We've had 27 minutes at Deepdale, and there is little to separate these two sides in this north-west derby.

Preston's Paul Gallagher has created several chances for his teammates but none of them have been taken.

Image source, Rex Features

Image source, Getty Images

Some breaking news to bring you from the Championship.

Chris Coleman has left his job as Wales boss to take over at bottom club Sunderland.

Coleman will succeed Simon Grayson, who was sacked after 18 games in charge.

Read more on this story by clicking here.

This game is unraveling for the home side - they've been forced into a change with Lloyd Dyer injured.

The winger went down and received treatment, but it was too much for him to continue and Lucas Akins has come on in his place.

Paul Gallagher creates another chance for Preston, clipping in a free-kick from 30 yards out.

Tom Barkhuizen flick a header just wide of the right-hand upright.

Burton started this one relatively confidently, but they're all over the place now with 22 minutes gone.

Billy Sharp is on the prowl and almost profits from another error, but Stephen Bywater grasps the ball at the second time of asking.

Leon Clarke then goes close for Sheffield United, but can only find the side netting.

More anxious moments for Bolton. Paul Gallagher's inswinging corner from the left is flicked goalwards from Andrew Boyle, but it goes all the way across goal.

Another let-off for the visitors in the opening 15 minutes at Deepdale.

The visitors have the ball in the back of the Burton net once again, but this time it doesn't count.

Jack O'Connell, who signed a new deal this week, heads in Paul Coutts' corner but it's chalked off for a foul on keeper Stephen Bywater.

Bolton come forward with purpose for the first time, Sammy Ameobi gets to the byline but his right-footed cross is straight at home keeper Chris Maxwell.

Antone Robinson then swings a cross in from the left but, again, it's easy for the keeper.

Here's the moment Billy Sharp gave Sheffield United the lead at Burton from the spot with his seventh goal of the season.

Image source, Rex

The hosts create the first chances of the evening, as Paul Gallagher works a short corner well and shoots straight at Bolton keeper Ben Alnwick.

Moments later the Scot's deep cross to the back post is put straight across goal by Lilywhites skipper Paul Huntington.

Billy Sharp is fouled in the box and Sheffield United have a penalty...