Goals from Toni Kroos, Thomas Mueller and Mario Mandzukic helped the Bundesliga leaders move into pole position to reach the quarter-finals ahead of the return leg of the last-16 tie at the Allianz Arena on 13 March.
Wenger’s position is coming under increasing scrutiny, with his side four points behind Tottenham in the race for a top-four finish and the Gunners looking set to extend their trophy drought into an eighth season.
But Vermaelen believes the Frenchman deserves credit for his impact at the Gunners since arriving in north London in 1996, insisting Wenger is the “right man” for the club.
“Of course we’re behind him,” said Vermaelen. “He’s done a lot for this club. He still does a lot of hard work with us. He is the right man for the job.
“We have to show it on the pitch as well. At the moment the results are not good. But we will work hard with him to get the results back.
“Everyone in football looks too short term. They don’t look at the long term, and he’s done a lot for this club.
“It doesn’t mean that because it’s not going well at the moment we don’t stand behind him.
“You have to look at the long term. He is the right man for this club and we are all behind him.”