It's a fine start to the game here! Liam Cooper loses the ball shoddily and Cambridge pounce, Piero Mingoia tees up Uche Ikpeazu on the left of the area and his low shot is easily pushed away by Marco Silvestri.

It's an excellent start from the League Two side though. 

Phil Shepka
BBC Sport

Early doors but this sell-out stadium is absolutely rocking to the drum of the Amber Army. Cambridge is sometimes seen as a quaint little place with its mass of bicycles and students.

But when this stadium gets going, the nearby river Cam could well be rippling.

Cambridge with the bright start but it's Leeds who go close to a fluke opener, Marcus Antonsson is running away from goal and lofts a cross on to the top of the crossbar and away. Cambridge keeper Will Norris was nervy at the end then...

Cambridge midfielder Luke Berry has scored 15 goals this season already and he's twice nearly in in the opening stages. Fifteen from midfield by January? Very decent. 

Image source, Getty Images

And we are off!

The teams are out. A reminder that Cambridge have won six and drawn one of their last seven and Leeds have made eight changes.

Is that upset on the air? Or the river Cam? 

Image source, Getty Images

Cambridge Utd: Norris, Taylor, Legge, Roberts, Adams, Newton, Dunne, Clark, Berry, Mingoia, Ikpeazu. Subs: Williamson, Dunk, Gregory, Maris, Pigott, Davies, Darling.

Leeds: Silvestri, Berardi, Jansson, Cooper, Denton, Grimes, Phillips, Dallas, Mowatt, Doukara, Antonsson. Subs: Green, Bartley, Roofe, Wood, O'Kane, Vieira, Coyle.

Referee: Craig Pawson (South Yorkshire)

Here we go then, a packed Abbey is rocking, I've seen face paint. We are good to go. 

Image source, Rex Features

Phil Shepka
BBC Sport

It's safe to say some of the Leeds United players haven't experienced anything like this before. 

As they came out to inspect the pitch before their warm up a couple came out wearing bright white shoes, which quickly became deep brown thanks to the mud.

The rain has been pouring down in Cambridge all day today, giving us a proper cup tie feel. It's abated now, but what impact could that have on the match? Will a Leeds side with so many changes fancy it?

A reminder that you can view the full draw - and have your say - on Facebook live. Get involved.

Image source, PA

Shaun Derry always had the air of a player who would go on to management.

The combative midfielder made 75 appearances for Leeds during a three-year spell at Elland Road, playing a key role in their passage to a Championship play-off final.

Image source, pa

The play-offs could well be back on his mind at the Abbey Stadium. After a rubbish start - they were bottom after eight games - they have clicked and are right on the tails of the top seven. 

Image source, PA

There are 38 places between the two sides in action tonight but with six wins and a draw in their last seven games, League Two side Cambridge will offer Leeds a stern examination.

Image source, Reuters

Leeds are going well though, they've lost just twice since mid October and are threatening a return to the Premier League for the first real time in a long time.

The away end at the Abbey will no doubt have a song or two for the Cambridge boss too...

Find out all you need to know about the 2017 FA People's Cup - and make sure you sign your team up. 

Entries are now open and you can find out all the details here.

Sam Gardiner: Class draw for @Boro, external. Man City or Accrington Stanley and we got Accrington. Could be our year #UTB, external#FACupdraw, external

Jack Gilmartin: These draws really aren't helping the FA Cup 'get back its magic'. Some of the most uninspiring cup ties ahead

Image source, Getty Images

• This will only be the fifth competitive meeting between these two sides and Cambridge are yet to defeat Leeds (D2 L2).
• The last time that Cambridge United and Leeds United met in a competitive fixture was back in April 1984, a game that ended 2-2 at the Abbey Stadium.
• Cambridge United have scored nine goals in the FA Cup proper so far this season; only AFC Wimbledon (11) scored more in the opening two rounds.

Not the most attractive draw in history - so let's move on to tonight's game.

You can get in touch with us here though on #bbcfootball or by texting in to 81111.

Fire away.

And that concludes the FA Cup fourth round draw. We thought we were on for Accrington Stanley v Man City for a while there...

Ties to be played between 27 and 30 January. 

Middlesbrough v Accrington Stanley

Crystal Palace or Bolton v Manchester City

Blackburn v Barnsley or Blackpool

Fulham v Hull