Derby have won 10 of their last 14 games, Leicester have won 10 games all season. 

See that form book though? Please deposit it out of your nearest window. It's the FA Cup after all.

Wes Morgan beats Darren Bent to his first header, Derby will look to build off the striker whenever they can.

Leicester have the first real attack but Shinji Okazaki slips over in the penalty area. 

Superstar ref Mark Clattenburg gets us up and running, he's presumably on his own road to Wembley.

And we're off! 

karmadrome: I know it's an early round cup match, but if the #LCFC, external players can't get up to play Derby, they don't deserve to wear the shirt.

Andy Townsend
Ex-Republic of Ireland international on BBC Radio 5 live

Jamie Vardy has suffered because of the lack of performances and confidence at Leicester. Teams defend that bit deeper against him now. He would punish teams week in, week out last season, but now he doesn't have the room to make the most of it.

Derby: Carson, Baird, Keogh, Pearce, Olsson, Hughes, Johnson, Bryson, Ince, Bent, Russell. Subs: Christie, Shackell, de Sart, Butterfield, Camara, Vydra, Mitchell.

Leicester: Schmeichel, Simpson, Morgan, Huth, Fuchs, Albrighton, Drinkwater, King, Chilwell, Vardy, Okazaki. Subs: Musa, Zieler, Gray, Mendy, Ndidi, Mahrez, Benalouane.

Referee: Mark Clattenburg (Tyne & Wear)

The rain is teeming down at Pride Park. Flags-a-waving, drums-a-beating, shock-a-ready? 

Image source, Reuters

Jay: When you have limited bullets, you preserve them for the important moments. Leicester doing just that with Champions League looming.

Former Manchester United and England midfielder Paul Ince: "Look at the way Leicester have been playing, they have conceded a lot of goals away from home. Derby will fancy their chances tonight."

Anyway, the players look ready and primed at Pride Park. Who are you backing tonight? 

We've all learned plenty about collecting trainers tonight. 

It's hard to get out of a rut and maybe a cup win tonight could be just the tonic that Leicester need.

Derby are flying though. Steve McClaren was very keen to play down any chat of the Rams being favourites tonight. But are they? 

Alan Shearer
Ex-England captain on BBC One

Jamie Vardy's head has been turned by success. I see him on the covers of magazines.

It's hard to get to the top but I tell you what it's even harder staying there. You need to do the hard work and Vardy, and Leicester, are not doing that.

They are not working as hard, they are not closing down or tackling anyone. 

Image source, Reuters

Leicester City

Leicester manager Claudio Ranieri: "When you win, the players get more confidence and we need that in this moment. We are a little bit sad.

"I am under pressure from myself. I want the maximum from every match and we want better for ourselves, the fans and the chairman."

Image source, Reuters

This is a montage of pain for Leicester fans. It has been a very poor Premier League defence but them's the breaks.

I think most fans would take a title even if it meant a relegation fight the year later. Right? 

Jake Young: Can see Derby getting a win tonight. Ince and Bent to run the show.

Chris Pinder: OMG this will need to be some game to beat Robbie Savage's hairdo!  

Tom Ince scored a fine goal at West Brom in the last round and Steve McClaren thinks that Leicester have played two left-backs tonight to stop him in his tracks. We shall see. 

Image source, PA

On this big weekend of FA Cup action, watch some of the best goals from the FA People's Cup - the UK's biggest free five-a-side tournament - and what it means to those who lifted the trophy.

You can get involved in the 2017 FA People's Cup, in one of 16 categories, now! Find out how to sign up here.

Former Derby midfielder Jeff Hendrick got himself a move to Burnley in the summer but he's tuned in. 

Derby manager Steve McClaren, asked if his side are favourites: "They are the Premier League champions! Of course they are favourites.

"It was always going to be difficult for them the year after winning the league but they have shown in cup competitions that they are still a great side. We need confidence and belief.

"Both teams have picked full-strength sides. We want to win and win on the night. Be aggressive and finish strong."

Image source, Getty Images