BBC Sport takes a closer look at two of the FA Cup's most successful teams, Everton and Manchester United, before their semi-final at Wembley on Saturday.
BBC Sport chief football writer at Wembley
"This is all or nothing for Everton manager Roberto Martinez - defeat in the FA Cup semi-final against Manchester United at Wembley may spell the end of his time in charge.
"And with that in mind, perhaps, he is taking a major risk by playing captain Phil Jagielka, who suffered a hamstring injury at Watford only a fortnight ago.
"Only yesterday Martinez said: "Medically I wouldn't accept Phil to be fit."
"Needs must, however, and with Ramiro Funes Mori suspended after his red card at Liverpool, Martinez is taking the gamble."
Manchester United fans, Everton fans, listen up.
Just how important is this game to your manager's future?
Does his future depend on a win here? Or not?
If he were to go, who would you like to see in the frame?
If he is to stay, what does he need to do differently?
Both managers are in the pressure cooker. One is about to pop.
Text us your views on 81111 (UK Only, with a name please) or tweet us at #bbcfacup
Motty's on the voiceover as the BBC One coverage kicks off. Watch at the top of the screen.
Manager Roberto Martinez has no plan B at Everton and defeat at Wembley would make it difficult for him to stay at the club, says former Toffees striker Paul Rideout.
Everton go into the game after a 4-0 defeat by Liverpool, which manager Martinez described as "horrific".
Rideout, scorer of Everton's winning goal in 1995 FA Cup final, said: "I think he knows he is in trouble."
Speaking to BBC Radio 5 live, he added: "I like the way he plays the game. I just think you have to have a little bit of the other side and I don't think he has shown that.
"You have to realise that it isn't working after several games and change it. As soon as Everton concede it is like 'oh, it is going to be one of those games'."
I am not an Everton fan, I have no affiliation to the club - but to be honest I would absolutely love to see a 90th-minute winner, at Wembley from Tony Hibbert.
He's spent more time on his carp farm than at Finch Farm this season...
Football is a kind of poetry, right?
Well today is the 400th anniversary of the death of William Shakespeare and our colleagues at BBC Learning have been playing with their ShakespeareMe tool to give us an idea of how the great man might have described the drama of an FA Cup semi-final.
Here's how his pre-match team talk might have looked. Maybe LVG will give this a go?Copyright: .
Have a go with the ShakespeareMe tool here - you enter your emotions and it comes up with a Shakespeare quote to match.
BBC Sport chief football writer
"Roberto Martinez deciding to take the big gamble on Phil Jagielka - admitted yesterday he was medically not fit but plays him at Wembley."
Everton make three changes from the team which were hammered at Anfield. Who plays at right-back? Besic?
We'll let you know once the game has kicked off. Darron Gibson, Phil Jagielka and Tom Cleverley are the men in.
Everton: Joel, Baines, Gibson, Stones, Jagielka (c), Lukaku, Lennon, Cleverley, McCarthy, Besic, Barkley.
Manchester United make four changes as both full-backs get switched and Michael Carrick and Marouane Fellaini come into midfield.
Manchester United: De Gea, Fosu-Mensah, Smalling, Blind, Rojo, Carrick, Fellaini, Lingard, Rooney, Martial, Rashford
You can WATCH live coverage of the FA Cup semi-final on BBC One and at the top of this page from 16:50 BST.
Alan Shearer, Kevin Kilbane and Louis Saha join Gary Lineker.
Alan Pardew and Quique Flores may consider themselves unfortunate to be even linked with speculation about their futures - but the fact remains that the combined record of Watford and Crystal Palace up to Christmas was: P34 W17 D6 L11.
Their combined record since Christmas is: P35 W4 D11 L20.
Those two face off on Sunday afternoon but for today it's all about Martinez v LvG...
As the Premier League title race and relegation fights rumble on we are concentrating solely on the grand old lady of competitions, the mighty FA Cup for the next few hours.
Who will be the first team to seal their place in next month's final?
Louis van Gaal.
Quique Sanchez Flores.
Four managers one game away from the FA Cup final.
Four managers potentially only a month or so away from the sack.
Whoever wins the FA Cup this year may get another crack at a season in the Premier League.
For the other three, defeat at Wembley this weekend could be the beginning of the end.Copyright: PA
Will Martinez leave the famous stadium smiling tonight? He has FA Cup pedigree after all...