The Latics were beaten by Maribor following Chris McCann's controversial red card and the Slovenian side progressed to face Sevilla in the next round of the competition.
Those two tems clash tonight and Rosler admitted he is envious of the Solvenian's for progressing as he told the Wigan Evening Post: "I was very disappointed that we lost that final game against Maribor, because we should have won it.
"I felt the referee took the game away from us that ight. It was our chance to play Sevilla, which would have been a great experience - I would have loved to have done that.
"On the flip side, having gone through what we have gone through in the last few months since I've been here, having another couple of league games rescheduled would have been very difficult to cope with.
"I really don't know how we would have finished the season had we got through."
The Latics travel to face Nottingham Forest at the City Ground this weekend in a fully rested state following a rare week without a mid-week clash.