The Serie A giants were narrowly beaten in France following Andre Ayew's stoppage time goal, but Milito believes that Inter have the quality to progress to the quarter-finals of the competition.
"We're convinced we can overturn the result. We played very well in the first leg and didn't deserve to lose. We're sure that we can win with the help of our fans," Milito said in an interview with Sky.
"We're sure we can still do well in the Champions League. Of course it is a different sort of competition. If we get through this round we'll be among the top eight teams in Europe.
"Tuesday's match is massive and we're desperate to do well. And after that we'll have everything to play for – this team have already shown they're capable of going all the way."
The second-leg encounter against Marseille at the Giuseppe Meazza kicks off at 20.45CET.
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