Celtic knew the importance of their victory over Rangers

Victory stretches Celtic's lead over the reigning champions to 11 points and Rangers boss Alex McLeish now believes his rivals can only throw away the Scottish title.

But O'Neill told BBC Sport: "The championship is in our hands, but we have a lot of difficult games coming up now and we still have to go to Hearts and to Aberdeen."

O'Neill also denied suggestions that there was an obvious gulf in class.

"I don't subscribe to that at all," he said. "I am absolutely delighted with the performance, we were absolutely excellent, but we needed it to be.

They can only lose the title, but we are a Rangers team and I am a fighter myself, so we will not give up Rangers boss Alex McLeish

"We look comfortable now, but a couple of defeats and you are back again."

A superb, Beckhamesque free-kick from Alan Thompson ensured victory after earlier strikes from Stilian Petrov and Stanislav Varga and his display in midfield will have impressed the watching England management team.

O'Neill thought it ought to lead to a call-up to his international side for Thompson.

Match report: Celtic 3-0 Rangers

"He was absolutely unbelievable and the goal epitomised his performance," said the Celtic manager.

McLeish was not being overly-critical of his own players, pointing out that Rangers knew they were going to be under pressure at set-pieces.

Alan Thompson (centre) will have impressed England selectors

"We had to match up Michael Ball against Varga, who is inches taller, so we were always going to be struggling," he said.

McLeish thought that the introduction of his new signing from Dundee, Gavin Rae, had showed signs of improving his midfield until the Scotland international had to go off injured after only 34 minutes of his debut.

"We started well, but the first goal put us on the back foot and the second was the killer," he said.

"There are two Old Firm games left and, with Celtic being 11 points clear, they can only lose the title, but we are a Rangers team and I am a fighter myself, so we will not give up."

Celtic defender Bobo Balde, voted BBC man-of-the-match, insisted: "It is a long way to go. Last year, Rangers were ahead of us by eight points and we ended up on the same points.

"We won today and it feels good, but it's not over."