It's been an underwhelming season for the two Premier League giants, with United finishing 19 points behind Manchester City and crashing out of the Champions League in the last 16.
As for Chelsea, they reached the same stage but will not be playing in the competition next season having failed to make the top four.
It's sure to be a tight game at Wembley and there's a sense that the game will be decided by who out of Paul Pogba and Eden Hazard turns up.
All eyes will be on the talismanic pair and Frank Lampard reckons if Hazard is the one who produces a masterclass, United will be in trouble.
"If the right Eden Hazard turns up he can be the match-winner," he said. "United are vulnerable at the back and Jose [Mourinho] will try to protect his defence, but Hazard could win it."
So what about Pogba? What if the Frenchman is able to dominate in midfield like everyone knows he can?
POGBA VS HAZARD
That remains to be seen, but heading into the FA Cup final Lampard has spoken the brutal truth about United's number six.
Lampard admits that Pogba is more talented than he was and would probably run rings around him, but he rightly states that means nothing if the 25-year-old can't produce decent numbers.
Furthermore, the Chelsea legend thinks Pogba has become a YouTube footballer and needs to stop trying fancy tricks in dangerous areas.
"I don't know what Pogba is," he said. "He makes bad decisions but then does fantastic things which must wreck Jose's head.
"Mourinho tried to embarrass him out of it and I worry Pogba did not get it.
"Pogba is naturally more talented than I was, he would run all over me and has better feet, but there's no point dribbling in your own half.
"All that 'flick and roll of the studs', I'm not an advocate of that. A lot of young players see it on YouTube and think it's amazing but I don't like it.
"He has delved to that side too much. His numbers are not good enough, he progressed at Juve but there's another progression he has to do.
"He should be getting 15 goals a season and dominating games, because he has everything."
Savage from Lampard - but he's absolutely right. Pogba has the potential to be a world beater, but he's focusing on the wrong side of his game and needs to get his priorities straight.
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