Per Mertesacker has warned Arsenal that their Premier League title hopes could hinge on how quickly they bounce back from Sunday's shock defeat to West Ham United.

Goals in either half from Cheikhou Kouyate and Mauro Zarate helped Slaven Bilic's new side stun the hosts with a 2-0 win at the Emirates Stadium.

Arsenal endured a slow start to the 2014-15 campaign and only discovered a sense of consistency after the new year, by which point a title tilt was out of the question.

Consequently, Mertesacker feels that it is "very important" for the Gunners to respond as soon as possible as they chase a first league crown since 2004.

"It's very important," he is quoted as saying by Arsenal's official website.

"We want to have a better start than last season so we need to be very cautious of the situation. To start with a game like that is not good but to bounce back is even more important now."

Next up for Arsene Wenger's side is a visit to Crystal Palace next Sunday.