Two further substitute appearances that season would see him play a total of 82 minutes of Premier League football with a handful of Cup games thrown in.
Since then O'Neill has had to look elsewhere for first-team football via loan stints with Oldham Athletic, Fleetwood Town and now Central Coast Mariners.
Still just 20, the midfielder has time to prove he's ready to grace the Premier League and is quickly picking up the necessary experience Burnley boss Sean Dyche demanded of him.
"You’ve got to go out and gain experience,” O’Neill told The Daily Football Show.
"That’s one thing the gaffer told me, ‘You’ve got to earn the right to be where these boys are, you’re not just going to walk in here and play, you’ve got to earn the right, earn the respect and then come in and show me you're ready to play in the Premier League’.
"As a youngster, I’ve got to push one or two players out and when they’ve been playing in the Premier League for two seasons now, that’s not easy.
"They’ve not just gone straight into the Premier League either, they’ve been playing League One, Championship.
"They’ve earned that reputation and earned that right to be playing week in week out in the Premier League especially at Burnley."
Having appeared in all three of the Mariners A-League games to date, O'Neill is quickly gaining valuable experience Down Under.
A 3-0 loss to Adelaide United in Round 3 a reminder that winning remains just as important as experience for any footballer.
“When it’s a big business, you’ve got to win games and you can’t teach players to win games, it’s game management and learning to get three points," he said.
“When you’re playing academy football, it’s completely different to first team football because if you lose, you developed well, or you kept the ball well.
“But if you don’t win, it doesn’t mean anything."