Phil McNulty
BBC Sport chief football writer at Wembley

Chelsea having pretty much all the possession in this second half but Crystal Palace are so well organised and showing great discipline.

They are trying to get Timo Werner to use his pace in behind the Palace rearguard but he has only had half-chances so far.

This FA Cup semi-final is turning into a real game of patience - especially as Palace still carry a threat on the break.

Cheikhou Kouyate gets up well to meet the corner but the ball comes off his shoulder and wide.

Image source, Getty Images

Wilfried Zaha sends a dangerous cross in from the right that Chelsea's defence has to head behind. The Crystal Palace fans ramp up the noise a notch as their side have a corner...

Jeffrey Schlupp stretches to try and beat Reece James to a ball but James wins out and Schlupp gets hurt in the process. Nothing serious, though.

Chelsea continue to dominate possession, looking for any sort of opening in this well-organised Crystal Palace defence.

Crystal Palace make their first change and it is in attack as Jean-Philippe Mateta is replaced by Jordan Ayew.

It was a tough shift for Mateta with not much to work with.

Ruben Loftus-Cheek surges forward and again tries to prod the ball between the defence, this time for Mason Mount, but Crystal Palace deal with the danger.

Ruben Loftus-Cheek stabs a good ball through the defence for Timo Werner to chase. The striker sticks out a boot but just can't quite reach as Jack Butland smothers.

Better though.

Mason Mount gets some power behind a shot from outside the area but unfortunately not the direction he's after as he sends it flying well over.

Chelsea appear to have come out with a bit - only a bit - more purpose, probably brought on by some harsh words from Thomas Tuchel at the break.

Crystal Palace, meanwhile, seem to have switched to a back five to counter the threat of Timo Werner. He was finding some spaces now and then.

Is this one destined for extra time? Or will we see some excitement in the next 45 minutes?

Chelsea get things back up and running.

Just in case we don't see many goals today - and that's looking a very real possibility - here's the highlights from yesterday's five-goal semi-final.

Clinton Morrison
Former Crystal Palace striker on BBC Radio 5 Live

Not many chances so far. Palace have grown into it; Patrick Vieira will be happy. Chelsea are dominating, but they are not creating much.

I was surprised Palace went to a back three to match up Chelsea, but it has worked so far.

Goalless at the break.

If I was being kind I'd call it a slow burner.

Antonio Rudiger is far too casual with a hooked clearance and he is closed down quickly but gets lucky with the bounce and eventually is able to do the job properly.

Owen: Still don't see why diving is seen as so much worse than intentional fouls, which are often described as 'clever' or admirably 'taking one for the team'.

Mark Burt: Even as a Chelsea fan, that blatant dive from Havertz was embarrassing. That level of simulation aka cheating deserves a straight red.

Joshua Thompson: Guehi is having an amazing game so far. Effortlessly stopping Chelsea attacks before they can get dangerous. Van Djik esque so far.