The 19-year old Australian striker, who was released by United in May this year, spent 10 days trialling with the Latics while Owen Coyle was in charge.
Coyle was sacked in early December, paving the way for Rosler to take the reins, and that did not deny Antelmi the chance to sign a deal with the North West club who he now hopes to develop his game with.
“I’m glad that nothing else went wrong after Owen Coyle left and the new manager came in,” he told au.fourfourtwo.com.
“I’m glad that they still had faith and also I’m guessing the coaches there that stayed obviously had faith in me and passed it on to the new gaffer.
“I was quite happy when I first walked in there. I think it’s a good club, good people and environment.
“With the new manager coming in now, (we’ve) just adapted to what he wants from the players and what he’s expecting from us. We’re learning from him and he’s learning from us.”
On his ambitions at DW Stadium, Antelmi added: “Just to get in the first-team as soon as I can.
“If that means to get some first-team experience on loan, before being able to make my debut for Wigan, then it’s something I will take and consider. I’d be happy to do that.To improve and to also to get seen to possibly get called up for the Socceroos, because that’s the dream isn’t it?”