West Ham boss Allardyce sees new steel in Arsenal defence
Allardyce believes Arsenal's defence has been strengthened since the recruitment of former Gunners centre back Steve Bould to the coaching staff.
He said: "It certainly looks a lot harder or more difficult to break down.
"People have said over the years that Arsenal have been weak at the back but the problem you face is getting to their defence.
"They're so good at keeping the ball that chances are few and far between."