Arsenal was defeated by Borussia Dortmund on matchday 3 of the UEFA Champions League but showed resiliency in the English Premier League by winning 2-0 over Crystal Palace despite going down with 10 men with 25 minutes left in the game.

Mikel Arteta pulled down Marouane Chamakh as the latter tried to break through on goal, to which the referee showed a straight red card.

Gunners defender Per Mertesacker disclosed the mindset of the squad coming into the game.

"We wanted to come back as quickly as possible as a strong unit. What we showed was good enough to respond," Mertesacker told arsenal.com.

The German wants to keep on proving the naysayers wrong by coming up with spectacular team performances but admitted that it might be a daunting task to sustain.

"But there will be more tests to come and that will be crucial for the rest of the season."

"We want to surprise people more and more, that is what we need to do but we do not look too much at the other sides. We are in a strong and interesting position, so we are aware of it and try to keep it - but that is the difficult thing, to keep it."

Mertesacker acknowledged the contribution of goalkeeper Wojciech Szczesny, particularly after Arteta was sent off.

The Gunners keeper made fine saves that led them to the needed victory.

"We had a decent goalkeeper as well, he saved three times when they were in a decent position,"

"We do not need the goalkeeper that much, but in those situations we do need him desperately. He did a good job, but the whole team did - and that is his job, to save us sometimes."

Olivier Giroud scored at the 87th minute to seal the deal for the Gunners.