With United's League One status secured, and the Latics with little to play for, manager Brian Laws is considering starting with the final year YT.
Lillis, son of former Iron striker and assistant manager Mark, has been offered a professional deal after impressive displays in the youth and reserve teams.
And the 19-year-old looks set to make his bow at Boundary Park this weekend.
Laws told BBC Radio Humberside: "We're considering whether to throw him in there.
Lillis could start at Oldham
"It would be a nice thing to do, if we do put him in the game he might make mistakes, might not.
"We can experiment and we've got to have a look at him, so we might just do that on Saturday."
"We can experiment and we've got to have a look at him, so we might just do that on Saturday."