Rosler now hopes that he can guide the Latics out of the Championship and into the Premier League.
"I wasn't expecting it," he told reporters. "Brentford were very helpful and when a big club like Wigan Athletic have given me this opportunity I couldn't turn it down.
"I am looking for stability and continuity in the football club. Over time that will bring success. This is a perfect opportunity for me to fulfil my dreams and ambitions to return to where I was as a player - the Premier League."
Rosler lost his first game in charge of Wigan 2-1 against Millwall at the weekend, but he has the chance to pick up his first win on Thursday against Maribor in the Europa League.