Celtic may be looking to trim their squad even further this summer. Here are three candidates for the chop...
Should the Norwegian stick to his word, however, more should be on the way out of Parkhead.
For starters, Charlie Mulgrew would seem the perfect candidate. There has been plenty of debate in the HITC Sport comments section on a recent article on the Scot's performance against Dukla Prague and, while some defend him in terms of his bad luck with injuries, plenty feel the 29-year-old is no longer worth his wages with the Bhoys.
Matthews is versatile but is he truly good enough to hold a place in the side down during a season that could involve Champions League football?
The Dutchman has been getting stuck in during pre-season training with Celtic but Derk Boerrigter's disappointments at Parkhead so far suggest he should be another man Deila deems dispensable at the very least.
Like Matthews, the winger is no longer the youngest of players (at 28) and there is a strong case to suggest he should leave the Hoops this summer.
A tricky one, as the 26-year-old can produce quality at his best.
But, if asked for a list of players they wouldn't mind seeing leave, Celtic fans are often quick to cite Anthony Stokes' name. Last season, he couldn't hold down a place up front, while the Bhoys have plenty of quality out wide, too.
James Forrest is another player to receive plenty of criticism at Celtic but, again, it's age that suggests it makes sense to give his potential a chance: he's three years younger than the hit-and-miss Stokes. Stefan Scepovic, too, could still make his mark if given more of an opportunity next term - making it even harder for the Irishman.