FA Cup final 2016: Lawro's lowdown on Crystal Palace v Man Utd

BBC Sport expert Mark Lawrenson

I see Manchester United dominating possession in Saturday's FA Cup final and Crystal Palace will have to play at a high tempo to disrupt them and cause them any problems.

Palace have played on the break all season, because they have quick forwards who can be their match-winners.

But United's patient approach will not see them committing many men forward, and opportunities for Alan Pardew's side to counter-attack will be few and far between.

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To be a threat, Palace will need to do more than sit deep, they must press United whenever they have the ball. If the Eagles can hurry them, and can force them back, they will give themselves a much better chance of scoring.

The first goal is absolutely key for Palace, not only because it would give them something to hang on to.

It would also mean United have to come out at them more, giving the Eagles more space to exploit the way they want to play, on the break.

If United score first, though, it is Palace who will have to take more risks and their own defence is far less convincing.

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Marcus Rashford is one of the few success stories of United's season but he had not even made his senior debut when they laboured to a 1-0 win over Sheffield United at the start of their cup run.

We have seen plenty of those type of performances recently - United have played far too much careful football under Louis van Gaal.

Being cautious in attack is not 'the United way' and their shortage of goals is one of the reasons they missed out on fourth place in the Premier League.

Their football is stifling, and playing backwards and forwards all the time is not enjoyable to watch.

But it does make them difficult to beat, and I also think there is something about playing at Wembley that suits them.

Even if it is actually the same size as several Premier League grounds, it always feels like there is more room on that pitch.

United played well there in their semi-final win over Everton, when there were spells in the first half that saw some of their best attacking play of the season.

Wayne Rooney, playing in the deeper role that has become his regular position, pulled the strings from midfield and he will be looking to do the same on Saturday.

Zaha will have something to prove

Wilfried Zaha celebrates Connor Wickham's goal for Palace in their FA Cup semi-final win over Watford
Zaha was Sir Alex Ferguson's final signing for United when he joined from Palace for £15m in January 2013, but he returned to Selhurst Park for the 2014-15 season, initially on loan

If he is fit, Rooney's former United team-mate Wilfried Zaha will be one of Palace's key men at Wembley. He definitely has something to prove against his old club too.

Zaha has just been voted Palace's player of the year and Pardew has praised his attitude, something that was called into question during his time at United.

Maybe the penny has dropped after the way things went for him at United, when I don't think he realised what a wonderful opportunity he had going there.

Whatever went wrong for him at Old Trafford, his ability was never in doubt.

He is still only 23 and could still have a very big career ahead of him, starting on Saturday if he can shake off a torn leg muscle in time to play.

Who will win?

Palace v Man Utd stats
Only relegated Aston Villa had an inferior shots-to-goals ratio than Palace in the Premier League this season

United will be in control of the ball and therefore they will be in control of the game.

For Palace to win they will need their whole team to function pretty much as well as they can do and I don't think they are playing well enough for that to happen.

They will have to stay tight at the back and score when they get a chance. Looking at the statistics, that is something they have done very little of in the past five months.

Their league form this year is awful and part of that is their lack of clean sheets - they have managed only two in 19 matches in the league this year. I don't see them keeping United out.

I know it is the cup final and a one-off game and we have seen shock results before - when Wimbledon or Wigan won, for example, but the way the two teams match up means this final has a different feel about it for me.

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Whether United win or not, I don't think it will keep Van Gaal in his job.

Their league position is the way this season will be judged and, by finishing fifth and missing out on the Champions League, it will be seen as a failure.

Nobody in a position of any prominence or power at United has said Van Gaal will be in charge next year. The only person saying that is Van Gaal.

But while winning the cup will not save him, it would still be important to the club and the fans.

Apart from the 2013 Community Shield, United have not won any silverware since Sir Alex Ferguson's departure as manager a few months earlier.

If they don't beat Palace on Saturday, it will be their longest spell without a trophy since the five years between their two FA Cups in 1985 and 1990.

The FA Cup would not be their first choice, but it does not really matter what the competition is - United are always a club that need to win something. This weekend, I think they will.

PREDICTION: MAN UTD TO WIN 2-0

Mark Lawrenson was speaking to BBC Sport's Chris Bevan.