He made 40 league and cup appearances, scoring 5 goals for St. Patrick's Athletic in 2010 and after a number of impressive displays he was attracting interest from further afield.
In November 2010, McAllister undertook a trial with Sheffield United which resulted in him signing a pre-contract agreement to move there permanently during the January transfer window.
[4][5] A few days after his move McAllister made his début for the Blades as a 75-minute substitute in an FA Cup tie against Aston Villa at Bramall Lane[6] but had to wait until late April to make his first league appearance, a game against Bristol City in which he scored his first goal for the club.
[9] He's done well for us, he's energetic, puts his foot in...He can play too, but we can't keep him longerthan the 93 days allowed so he'll have to return toSheffield United before the end of the season.
[15] McAllister's impressive run was temporarily halted at the end of March when he incurred a red card, being controversially sent off against Aldershot Town.
He began to make regular starting appearances and scored the only goal against his previous loan employers Shrewsbury Town in the opening game of the season.
[19] Having played regularly until November McAllister lost his place once more and deemed a fringe player, was allowed to leave as United looked to trim their squad.
[20] In January 2013 McAllister completed a move League One rivals and former loan club Shrewsbury Town for an undisclosed fee, signing a two-and-a-half-year deal.
Initially it was a surprise that they would sell him as he's figured in a lot of their games, but I think the fact that he has been here and knows all about us, knows the professional attitude and the work ethic here helped in his decision to join us.