The 21-year-old has made two first-team appearances for Bolton, whilst also enjoying loan spells at Sheffield United and Carlisle. O'Halloran's only league start came for the Blades in a 2-2 draw against Stevenage in April.
Just when you thought this transfer would roll towards its seemingly inevitable conclusion when Paul Pogba returns from holiday in
He is a player that shows big promise but is not first choice with bench-warming duties too often his fate
Sam Allardyce has been officially unveiled as England's new manager, charged with guiding the Three Lions through their World Cup
ARSENALManager: Arsene WengerPosition last season: 2ndNickname: The GunnersGround: Emirates StadiumCapacity: 60,432Players In: Granit Xhaka (Borussia Monchengladbach, £35million), Takuma Asano (Sanfrecce
ASTON VILLAManager: Roberto Di MatteoPosition last season: 20th in Premier LeagueNickname: VillansGround: Villa ParkCapacity: 42,660Players in: Tommy Elphick (Bournemouth, £3million),
He was one of many surprise packages at Leicester that elevated the club to the top of the Premier League