Giovanni van Bronckhorst branded his Rangers side’s first half display shambolic and admitted it was like his players were experiencing the Old Firm derby for the first time.
The shellshocked Ibrox boss couldn’t believe the goals the champions conceded as they went in 3-0 down at the break after a first half Celtic blitz.
Reo Hatate bagged a double and Liel Abada netted to move the Hoops a point clear of their rivals at the top of the Scottish Premiership.
And Van Bronckhorst told Sky Sports: “Very disappointing. If you start an Old Firm game like this…it seemed like it was the first Old Firm we’d played.
“You know what you have to do, the environment we go into, the atmosphere, the pressure, everything, but we didn’t seem ready for it.
“If you see the goals we gave away. It was sharpness - I can’t say otherwise. Not going with your man, not being ready for the battles.
“It was unbelievable what I saw in the first half and our Old Firm game started in the second half where we were much better and more aggressive.
“But we gave the game away in the first half. I didn’t expect it when I watched training and the focus we had before the game.
“When the whistle blew we were just waiting for the goal to be scored and were too naive and deserved to be down 3-0 the way we played.
“We had an honest conversation in the locker room after the game. It wasn't the way we wanted it, especially in the first half, but we have to stick together and make sure we move forward and we’re ready for Hearts on Sunday.”
Van Bronckhorst was thumped 5-1 at Parkhead in his first season as a Rangers player but ent on to win the title.
And he said: “It’s a tough environment to come into but we’re not the first Rangers team to lose. I lost heavily here but we became champions.
“Of course we wanted to win this game but they don’t decide the championship. We still have many games to play and have to be ready.”
Gers players called for play to be stopped in the build up to Celtic’s first goal after a clash of heads involving two of their own players but Bobby Madden continued despite a head knock.
And Van Bronckhorst insists his players should have played to the whistle. He said: “It’s the decision for the referee to stop the game.
“We still had the corner to defend, the ball goes out and you have to defend the ball - you don’t stop if the ref doesn’t whistle. That’s unbelievable to see.”
