Ryan Jack has confessed lacklustre Rangers didn't get anywhere near close enough to rampant Celtic.
The midfielder admitted the Ibrox side got what they deserved in a heavy defeat at Parkhead.
Ange Postecoglou 's side raced into a 3-0 half-time lead and have now leapfrogged the champions at the Premiership summit.
And Jack, who came on as a sub at the interval, insists it just wasn't good enough.
Rangers fans were furious at how passive their team were in the opening 45 minutes and it's the very term Jack used to describe their display.
He told Rangers TV: “We’re very disappointed. We let ourselves down massively and it’s a sore one to take.
“But us as players and a group of men we need to stand up and address that and pick the bones and see what’s going on defensively and what we can do better.
“Sunday is going to be another tough one for us as players and we need to lead, stand up and be counted.
“We weren’t close enough to them. We were too passive, standing off and weren’t making tackles.
“Historically, this fixture is about winning the battle first. It’s always a battle, especially coming to Celtic Park.
“The fans and the crowd are up and you know it’s going to be a battle. We never turned up and on the flip side we conceded the goals which were bad to lose.
“We need to stand up and come Sunday there needs to be a reaction because Hearts will be thinking we’ll be feeling the effects.
“I don’t really think there were positives to take from the second half. We were pushing and you can’t see positives because it’s raw but my shot hit the bar and if someone went in we might have got a reaction and might have made it a bit more nervy but it never came.
“We’ve let ourselves down and the club and the fans and we need to come right out the traps on Sunday.