Noel Whelan suggested Scott Brown held crisis talks with fellow established Celtic players following the shock loss against Sparta Prague on Thursday.
Speaking exclusively to Football Insider correspondent Dylan Childs, the former Aberdeen and Leeds United striker insisted that a “culture change” is needed at Parkhead in order to eradicate “inconsistency”.
The Hoops bounced back from a 4-1 defeat at home to Sparta Prague in the Europa League by beating Motherwell by the same scoreline on Sunday at Fir Park.
Two wins from seven have left Neil Lennon’s side nine points adrift of Rangers in the title race, as well as bottom of Group H in the Europa League.
Whelan warned the Hoops that the title will escape them if they do not quickly rediscover their hunger and desire.
“I think there was a few words said by Neil Lennon to the players after the Sparta Prague game,” he told Football Insider.
“I am hoping that Scott Brown and the more established Celtic players, those that have been there for a long time, have had a private meeting in the changing room as well.
“It is not acceptable for Celtic to be this complacent. Usually they are a lot hungrier.
“There is a culture change that needs to be had at Celtic, much like they have had at Rangers because they are unstoppable at the moment – relentless.
“It is the inconsistency that is frustrating Neil Lennon. That has to change. There needs to be more hunger and desire.
“It needs to come back and come back soon, because if not the league will drift away from them.”
In other Celtic news, Gabriel Agbonlahor cannot believe the Neil Lennon claim made by his talkSPORT colleague.