A tactical change but one forced by an injury because midfielder Valon Behrami is coming off. 

His replacement, captain and striker Troy Deeney, has been stuck on 99 goals for Watford since October... Is today the day? 

Two changes within the first 15 minutes for the home side!

First shot on goal to speak of and it's a poor one as Andros Townsend scuffs a low strike wide from outside the box. 

What's this though? More injury woe for Watford? Midfielder Valon Behrami's down now, he's getting treatment from the physios and there is movement in the Hornets' dugout...

Alistair Bruce-Ball
BBC Radio 5 live

I have just remembered, I commentated on the Boxing Day fixture here at Vicarage Road last year and had to borrow a baseball cap from the club shop because of the low sun shining straight on the commentator's position... 

I have forgotten to do that this year - bear with me. 

Watford have barely had a sniff of this. Their first passage of passing play peters out when Etienne Capoue plays a loose ball forward that's snaffled up by Wayne Hennessey.

Image source, Getty Images

I tell you what though. These first few minutes from Wilfried Zaha have been seriously impressive. Again he's in down the left but his cross is slightly wayward.

Something to prove to the new gaffer?

Cabaye's crossed free-kick is flicked behind by Adlene Guedioura.

Corner ball, which is flapped at by Heurelho Gomes. Corner again, but there's a foul in the box and Watford can breathe. 

Wilfried Zaha coasts his way past the rusty Juan Zuniga and is tripped right on the edge of the box by the second challenge of Adlene Guedioura. 

Good start this from Palace. Yohan Cabaye could do some damage from here...

Image source, Reuters

After some lengthy treatment, Daryl Janmaat is coming off on a stretcher. Looks like a muscle problem? 

Juan Zuniga, the Colombian wing-back, is on to replace him in a like-for-like change on the Watford right.

BBC Radio 5 live

Don't forget, you can listen to Radio 5 live commentary of this match right now - with Sir Trevor Brooking summarising alongside Alistair Bruce-Ball. 

An early dart down the left flank bags Palace an early corner. Delivered into the fray by Yohan Cabaye, plucked from the sky by Heurelho Gomes. 

Daryl Janmaat gave the corner away sliding in to block Wilfried Zaha. 

Now Janmaat's down. Has he pulled something? This doesn't look good for him.

We are under way. 

There he is, former England boss Sam Allardyce. Handshakes out of the way, he's taken up his place in the Palace dugout, collar up, chewing gum on the go.

Down to Vicarage Road now though. Last calls in the tunnel. 

Heurelho Gomes is leading the Hornets out into the Boxing Day sun, with captain Troy Deeney dropped to the bench. Will he come on and finally bag his 100th goal for the club?

The Sam Allardyce era is about to begin for Crystal Palace...

Simon Stone
BBC Sport

West Ham owners David Sullivan and David Gold are not looking for any additional investment, BBC Sport understands, despite reports of a possible takeover.

Drinks giant Red Bull is reported to be considering a £200m offer, external for the Premier League club.

Sullivan and Gold bought a majority stake in West Ham in 2010 in a deal that valued the club at £105m.

Between them they now own over 85% of the club.

Full story.

Image source, Getty Images

Trevor Sinclair
Ex-West Ham winger on BBC Radio 5 live

They talk about Dimitri Payet in the same breath as Paolo di Canio, a cult hero. Payet's not been rubbish this season, a lot of West Ham players have been under par. The move to London Stadium just hasn't happened for West Ham.

Image source, Rex Features

Also, there's a bit of Russell Beardsmore-related chat to squeeze in... (see 11:31) 

Earlier we were asking for your photos and stories of football present fails...

This one making a late entry into the most broken windows category. 

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BBC Weather makes it about 7°C at Vicarage Road. Positively balmy. I've even seen someone in shorts. 

A short journey for the travelling Crystal Palace fans. Spare a thought for the Swansea supporters going across to West Ham and back later on Boxing Day...

As we all start thinking about cranberry sauce etc, let me remind you: 15 minutes to go until kick-off at Watford. Get your maneouvres in sharpish. 

Oh dear...

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