Celtic boss Ronny Deila says keeping his best players will take priority over acquisitions in the transfer window.
Chelsea striker Fernando Torres is understood to be set for a return to Atletico Madrid, according to Sky sources.
Richard O'Kelly has stood down as boss of Hereford after rejecting the chance to manage the club in the Blue Square Bet Premier.
O'Kelly replaced Jamie Pitman in early March and was handed the task of keeping the relegation-threatened Bulls in League Two, but three wins, four draws and five defeats from his 12 games in charge was not enough.
Hereford find themselves back in non-league football for the first time since 2006 but, after being given the opportunity to try and guide the club to promotion, O'Kelly has turned down the offer.
Chairman David Keyte told United's official website: "We're disappointed that Richard has decided his future doesn't lie with us. But we'd like to thank him for his efforts during the last 10 weeks.
"Our task now is to find someone who does want to be manager of Hereford United."
O'Kelly, despite boasting vast experience in coaching and as an assistant boss, had never held a senior management position before taking the role at Edgar Street on a deal until the end of the season.