Giroud gave the Gunners the lead on the stroke of half-time with a fine finish, before Aaron Ramsey made the points secure when he fired home in the 81st minute after some intricate build-up play from the north London side.
Substitute Mathieu Flamini added gloss to the scoreline when he tapped in from close range following Santi Cazorla’s low pass across goal.
Giroud has now scored seven goals and made three assists in his last 10 games in all competitions for the Gunners.
And Wenger was full of praise for the 28-year-old forward after the final whistle at Emirates Stadium.
“Giroud had an outstanding game today,” Wenger told his post-match news conference.
“[Responding well] it’s one of his strengths. This is a boy who has played at 22 or 23 in division three.
“He’s come out and has become an international footballer. You need some mental strength to do that because there’s no red carpet there. You have to work hard to get out there and get to the top – you need some special strength.”
Arsenal travel to Monaco looking to overturn a 3-1 deficit from the first leg of their Champions League last-16 tie on Tuesday.
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