'Arsenal win would be a shock – Mertesacker is playing!'

Paul Merson believes Arsenal's chances of beating
Chelsea in the FA Cup final are extremely low,
particularly with Per Mertesacker set to play as the
club cope with a defensive crisis.
Arsenal meet Chelsea at Wembley on Saturday
looking to salvage silverware from a season that
has seen them fail to qualify for the Champions
League for the first time in 20 years.
Laurent Koscielny is suspended, Gabriel is out
injured and Skhodran Mustafi is a doubt following a
concussion – a combination of events manager
Arsene Wenger described as "absolutely
unbelievable".
Mertesacker is therefore set to start for the first
time in over a year in the biggest match of
Arsenal's season, leaving former Gunners star
Merson far from confident.
"Arsenal are struggling in defence," Merson, who is
predicting a 3-1 Chelsea win, told Sky Sports.
"If both teams had brought their A game then
Chelsea would still have won, but with Laurent
Koscielny and Gabriel out, Shkodran Mustafi
potentially out and Per Mertesacker playing at the
back I would be shocked if Arsenal got a result.
"With Arsenal's defence, I can't see them coping
with Chelsea's attacking flair. We saw Tottenham
play very well in the semi-final and they still let in
four goals. Tottenham were the better team on that
day and still lost.
"Arsenal need to have their best defenders playing
to have any chance and they haven't."
On Wenger's options, Merson added: "I think the
missing players will mean Arsenal have to go four
at the back. If Mustafi plays, they could play him
with Mertesacker and Rob Holding as a three. But if
he doesn't then you only really have Mertesacker
and Holding.
"If you start playing Nacho Monreal as one of the
three then he won't be able to cope with Diego
Costa.
"They would have to play Mertesacker in the
middle because of his lack of pace and then
Chelsea would play diagonal balls to Costa who
will sit on Monreal and he will win every header
and they will go from there. It's a dangerous one
for Arsenal if they play three at the back.
"Mertesacker is going to be crucial for Arsenal if he
plays; he will have to play very well if Arsenal are
to have any chance. If he doesn't play well then
Chelsea are going to cut through Arsenal like a
knife through butter."
Arsenal beat Chelsea 3-0 at Emirates Stadium in
September, but suffered a 3-1 loss in the return
fixture.