Neil Lennon blamed laziness on Celtic's failure to take pole position in the Clydesdale Bank Premier League title race in Inverness on Wednesday night.
The Hoops only needed a draw in their game in hand against Caley at the Tulloch Caledonian stadium to leapfrog Rangers at the top of the table but there were few who would have bet against an away win.
However, a shock 3-2 defeat for the Parkhead side handed the advantage to the champions who still lead by one point with three games remaining.
The Celtic boss seemed still to be frustrated as he reflected on the trip to the Highlands while preparing for tomorrow's game against Kilmarnock at Rugby Park.
“We analysed the game and the goals,” said Lennon.
“We started the game well and had four corners in four minutes but the first time Inverness put the ball in our box we are lazy.
“The first goal is very lazy defending from our point of view.
“We are trying to play offside — which we don't do anyway — and we didn't get back in to position quickly enough to deal with the cross or stop it. It was lazy. Just lazy.
“I don't think it was anything to do with nerves. It's about not doing their jobs properly, not seeing the danger.
“We cleared our area but when ball is not completely cleared we were not switched on.
“The second goal is a good finish but in the third goal they have gone AWOL again. Just basic mistakes from very good players.”
Despite his criticism of his players and Rangers' advantage, which could be stretched to four points if they beat Hearts at Ibrox today, Lennon believes a title win is still achievable.
“It's not over, it's still up for grabs,” said the former Celtic skipper. There is one point in it and three games to go so we are still really in it.
“We have to win the games and force Rangers in to winning theirs.
“There is a lot of football left and anything can happen and we have just got to defend as a unit a lot better than we did on Wednesday and we will be okay.
“We were flat after Wednesday but the players have picked up again and are very motivated. Rangers have to win as well and if they slip up, we have to be ready to take the chance and we will.”