Former Celtic defender Adam Virgo has told The Scottish Sun that the Bhoys have in fact moved backwards under Ronny Deila.
The Bhoys moved to bring in Deila from Norwegian club Stromsgodset in the summer of 2014, having seen Neil Lennon leave the club after three successive title wins.
Deila arrived having worked wonder with Stromsgodset, but his reign with Celtic got off to a tough start having missed out on Champions League qualification following defeat to Maribor - but much of that was chalked down to him finding his feet in Scottish football.
Winning the title and the Scottish League Cup last season certainly helped him, but problems in Europe have again arisen this term, having been beaten by Malmo in the Champions League play-offs, whilst they are also struggling in the Europa League after a 3-1 thrashing at the hands of Molde last week.
Deila is now under increasing pressure, with Celtic fans believing that it is no longer enough to just win the Scottish Premiership title, with European success needed as well.
Now, former Celtic defender Adam Virgo has been asked by The Scottish Sun whether Deila has taken Celtic as far as he can - and he even believes that the Bhoys are moving backwards under Deila, having witnessed their struggles in Europe.
"To me Celtic haven’t moved forwards since Neil Lennon left," said Virgo. "Winning the league is always a must but in Europe I don’t think Celtic have improved at all. In fact they have gone backwards and missed out on the Champions League again," he added.