Mullen completes Hibs move
Celtic manager Neil Lennon has insisted he will not rush Efe Ambrose back from international duty after learning from the experience of last season.
The defender declared himself fit for a UEFA Champions League game against Juventus in February after flying in from the Africa Cup of Nations, but produced a poor performance in a 3-0 defeat and was even criticised by team-mate Kris Commons.
He has been away with Nigeria again this summer, at the Confederations Cup, and Lennon has promised that this time he will not come back too soon.
The Celtic boss says Ambrose needs some time off ahead of the new campaign, even if that means he does not play much of a role in pre-season.
Reflecting on what happened against Juventus, Lennon said in the Sunday Mail: "Aye, we'll learn from that one.
"He won't be back until the 15th, so he'll miss a huge chunk of pre-season.
"Efe's a fine athlete but he needs rest."
The 19-year-old, who left Tynecastle earlier this summer before the Gorgie side entered administration, is Pat Fenlon's fourth signing of the summer.
Mullen has represented Scotland at Under-17 level and joins Owain Tudur Jones, Liam Craig and Ryan McGivern as Hibs' summer signings.
A statement on Hibernian's website said: "Hibernian can confirm the club has signed defender Fraser Mullen on a one-year contract.
"A former Scotland under-17 internationalist, right-back Mullen, 19, agreed the deal on Saturday morning and has become the club's fourth arrival during the summer transfer window."
Hibs will depart for a training camp in southern Europe on Monday afternoon following their 1-1 draw with Dumbarton in their first pre-season friendly yesterday.