Goals from McArthur and McCann put the Latics in pole position in the game before a consolation goal for Brighton left the result at 2-1 and put Rosler's men within a point of the play offs.
Speaking to the club's official website, Rosler said: “First of all I would like to dedicate the win to Ben Watson. The team coped very well without him today and they showed character in what is a big loss to the group.
“I’m just delighted for the boys and to be able to dedicate it to Ben. Our thoughts are with him after he had his operation yesterday and we’ll look forward to seeing him next week.
“To come here to Brighton and get a victory is a very good achievement. I’m very happy with how we won the game, especially here in Brighton in such an important game against a side who are very good at home.
“You could see how much both teams wanted to win the game, so for us to take all three points is a sign of how much desire my players have."
Watson's injury aside and it was a successful week for the Latics who moved to within a point of the playoff places with a game in hand over sixth placed Reading.
Next up for the Latics is a tough test to visit Nottingham Forest next Saturday.