The Germany international has been one of the north London side’s standout performers this season as the Gunners continue to keep pace with their rivals in the title race.
When you listen to what people said when he arrived and how people speak about him today, all that credit is down to him
Mertesacker, who moved to The Emirates in a reported £8m deal from Werder Bremen in 2011, made 21 top-flight appearances in his first season at the Gunners.
However the 6ft 6ins defender has improved markedly in the past two seasons, and Mertesacker has regularly captained the Gunners this season in the absence of Mikel Arteta and Thomas Vermaelen.
“He is one of the important players of the squad,” said Wenger.
“When you listen to what people said when he arrived and how people speak about him today, I think all that credit is down to him – his intelligence, his dedication and his huge desire to win things.
“He is a human being with an exceptional attitude and it is rewarded through that.
Wenger continued: “When his game was questioned he responded very strongly and in a very intelligent way.
“What you want from a football player is that he gives everything possible and that is what Per is all about. He characterises the team well because all the players have a fantastic attitude.”
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