Mertesacker calls out teammates ahead of showdown with United

Per Mertesacker has challenged his Arsenal teammates to show more aggression on Sunday as the Gunners look to recover from their latest European flop by hosting Premier League leader Manchester United.

Arsene Wenger's side dropped an embarrassing 3-2 decision at home to Olympiakos in midweek that left it in severe danger of missing out on a place in the Champions League knockout stages for the first time in 16 years.

Adding to the Gunners' humiliation was a horrendous blunder by goalkeeper David Ospina, who dropped a corner into his own net to gift the Greeks their second goal and in the process triggered a barrage of criticism for Wenger for his decision to rest regular starter Petr Cech.