Neil Lennon threatened to "out" the Celtic players who might cost him the Clydesdale Bank Premier League and his job, as the Hoops dropped 12 points behind Rangers after a lacklustre goalless draw against Hibernian at Parkhead.
Gary Hooper and James Forrest both hit woodwork for the Hoops but it was an afternoon of frustration against a side Celtic had beaten 4-1 in the Scottish Communities League Cup quarter-final tie in midweek. With Rangers winning 2-1 against Aberdeen at Pittodrie earlier in the day, Celtic's title hopes took another bruising.
The Celtic boss said: "I am really angry, they let the game drift away from them and that is not acceptable."
He added: "I would like to make changes but the way the squad is stretched it is difficult to do that.
"There are a few who have been consistent like Ki and Joe Ledley but there are others at the minute who are happy to go along, riding on their backs and not really making the contribution that I want from them.
"I have to speak to them and out them, basically. I am not happy with some of them at the minute.
"I don't think they are giving enough in terms of the quality of their play or effort and I will speak to them individually and tell them what I think and I am looking for a response from them. But you ask them questions at times and you don't get answers."
Colin Calderwood watched his side improve markedly from Wednesday to enjoy more than their fair share of possession but the Hibs boss claimed it would have been greedy to have looked for three points.
The former Scotland defender said: "I am very happy. We got better as the game went on and used the ball better.
"It was a good point at a difficult place and psychologically being able to keep a clean sheet after losing four in midweek is a good help. I enjoyed the way we played. To go from one level to this one is very encouraging so I don't think we can be too greedy."