Hearts interim manager Jon Daly launched a remarkable attack on Brendan Rodgers over claims made about the Jambos before their 4-1 defeat at Celtic Park.
Daly was put in charge after head coach Ian Cathro was sacked in midweek and before the match the Hoops boss expressed his empathy.
However, Rodgers also questioned the recruitment policy at the Tynecastle club, saying: "He is trying to play football and you are bringing in players who play a direct game. So it makes me ask about where the players are coming from or if they are his."
Following Celtic's easy win in the Ladbrokes Premiership opener - striker Leigh Griffiths grabbed a double with Scott Sinclair and Callum McGregor both also scoring - Daly came out firing.
He said: "It is absolutely disgraceful.
"I think it is very poor form. A manager of his calibre should know better.
"I followed Brendan's career when he was at Liverpool and never once did I hear him make a comment about Man United's structure, about Chelsea, about Man City's structure, but all of a sudden he comes to Celtic and he thinks it is acceptable to talk about the structure of our football club.
"Our club at the moment is very easy to pick on and kick, but for a manager of his calibre to come out and make the comments he did was unacceptable.
"I can understand the comments made about the manager leaving but once he starts talking about the recruitment of players, fitting into the system and questioning Ian's authority, it shows me he doesn't know Ian Cathro very well.
"There is no chance that any of those players that came in the door would have come in without Ian's say-so.
"Brendan is a knowledgeable man. The fact that he thinks Michael Smith, Kyle Lafferty, Christophe Berra, Rafal Grzelak, Connor Randall don't suit a 3-4-3 system baffles me. It really does.
"We have wing-backs, strikers, centre-back, combative midfielder, it is actually farcical that he thinks they didn't fit into that system and the fact that he thinks that other people around the club makes the calls and to comment on it is an absolute disgrace."