Arsenal defender Per Mertesacker admits they cannot afford a slow start today against Stoke City.

He accepts the Gunners must be ready to match Stoke's challenge from kick off.

"I hope to adapt quickly to Stoke and the situation and the way they play," Mertesacker told Arsenal Player. "We have to switch on quickly and do the right thing.

"We have done a lot of things [in training] concerning set pieces, throw-ins and crosses.

"We have to cover each other even more than the other games because they are very dangerous players, especially up front, and very tall players.

"Maybe we have to behave differently, but we always want to show our own qualities."