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 and although they have a game in hand Lennon is at the end of his tether.

The Celtic boss said: "I am really angry, they let the game drift away from them and that is not acceptable.

"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."

Lennon pointed the finger specifically at striker Anthony Stokes and Hooper.

"I thought the two of them were poor today and I need some more consistency from them," he said.

"If they are not scoring goals they need to bring something else to the team and I thought the two of them were very flat today."

The Irishman insists he is not concerned about his position - just yet.

He said: "The only way I would leave the job this season is if I decide I am not taking the club forward or I am not getting the performances that the fans merit.

"When you come in 3-0 down against Kilmarnock at half-time, or against any SPL side, you have to ask questions about myself.

"Today, I am not hugely concerned about my position, it's more of a question of why I can't get these players to be as consistent as last season."

Celtic defender Mark Wilson claimed his manager's words were "harsh" but admitted the dressing room is aware they could get Lennon the sack.

He said: "There have been far too many of these days this season and we have shot ourselves in the foot again

"It was a very bad day for us. It is harsh words but that's what he thinks.

"I don't like slagging my team mates off but we have to do better.

"Football is a result-driven game but we don't want that (Lennon sacked).

"We are firmly behind the manager and we love working him and the coaching staff.

"We are under no illusions that it is a possibility but it us up to us to repay the faith he has in us and we haven't done that so far this season."

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."