Celtic 1-1 Rangers: We were denied clear penalty - Brendan Rodgers
Celtic boss Brendan Rodgers felt his side were denied a "clear penalty" as they drew 1-1 with Rangers.
Leigh Griffiths appeared to be pulled down by Clint Hill inside the area in injury time, but referee Bobby Madden refused appeals for a spot-kick.
Rodgers said Hill, who scored the late equaliser, admitted to him after the game that he "got away with it".
"It's very disappointing that with four officials they don't see that. It looked a clear penalty," said Rodgers.
"Clint Hill said on the pitch to me afterwards that he got away with that. Clint's a good guy, an honest fellow."
Rodgers said the concession of the equaliser so late on made the draw feel "like a defeat", but he said he was proud of his team's performance.
Celtic opened the scoring in the first half through Stuart Armstrong's rifled shot from the edge of the area, and the midfielder had two second-half efforts saved by the Rangers goalkeeper Wes Foderingham.
Griffiths, a second-half substitute, also had a shot headed off the line before the final whistle as the Premiership leaders' run of 22 consecutive league victories came to an end. They remain undefeated in 35 domestic games this season.
"On a difficult pitch I felt we weren't as fluent as usual in the first half," Rodgers told BBC Scotland.
"I thought we took the easy option on the ball. We were passing backwards and sideways instead of forwards. We made a change at half-time and I thought we had much better control in the second half and we looked like we were going to go on and score more goals.
"The boys have been on a brilliant run but this will help us in terms of preparation for the Scottish Cup semi-final [against Rangers on 23 April].
"We will just re-focus again. We are a strong team and we will take that into the next games.
"I don't think the team are complacent but when you concede like that, it just makes you realise you have to be fully focused and make no mistakes. Sometimes you can make mistakes and get away with it."
Rodgers described Armstrong's performance as "excellent" and acknowledged the team lost "a little bit of control in the middle of the pitch" after the midfielder was substituted because of a tight calf.
The midfielder, pushing for a place in the Scotland squad announced on Monday for the forthcoming games against Canada and Slovenia, said the Celtic players need to keep their perspective, despite the disappointment of conceding late on.
"It says a lot about our season so far and how well we have been doing that coming away with a draw feels like a loss," Armstrong told BBC Radio Scotland.
"But we need to remember where we are and how well we are doing. We are still on a good run of form and we need to keep that going.
"These games are always high-pressure and a bit hectic. We tried to keep our composure but the pitch is a bit bobbly at the moment and it is not how we want to play.
"But we produced some good football in parts and we need to keep our heads. It feels very disappointing to lose a goal so late on but we will stay very confident for the rest of the campaign."