And the Dons boss is adamant that television evidence will support his claim that a last-gasp strike from Zander Diamond should have stood and earned his side a share of the spoils at Parkhead.

The effort was disallowed because the official claimed Diamond had handled the ball before being set up for the shot by Barry Nicholson, claims which have been refuted by the Aberdeen camp after watching replays of the incident.

Instead, a Georgios Samaras goal in the second half proved to be decisive and allowed Celtic to move two points clear at the summit of the SPL, albeit challengers Rangers have three games in hand.

Diamond was clearly unhappy with the referee's decision at the end and Calderwood says the only reason he did not dispute the judgement was to avoid another fine from the Scottish Football Association.

"I've spent enough money there," he said.

"I vowed not to go to Hampden again unless it's as a Scotland supporter so I didn't get involved, which is not easy. I let Jimmy Nicholl (assistant manager) get on with it.

"The referee was adamant that we would see on television that it was a handball from Zander Diamond.

"But he knocked it on with his head and I've just heard from the television people that there was nothing in it at all.

"The referee was adamant so it will be interesting when he sees it on television.

"We could have nicked a point which, in the circumstances, would have been wonderful for us after the last seven days."

Aberdeen headed into today's match still reeling from their Scottish Cup semi-final exit at the hands of First Division Queen of the South last week.

And Calderwood knew it was not going to be Aberdeen's day yet again when a Scott Severin shot hit both posts before being smothered by goalkeeper Artur Boruc early on, with assistant referee Billy Baxter claiming the effort did not cross the line.

Calderwood said: "Celtic had a lot of possession in the first half but we had the best chance when the ball hit the inside of the post twice.

"With the spin on the ball, you would think it would go over the line. But, with the week we've had, starting with last Saturday, it's just not going to go for us."

Calderwood now predicts a nerve-jangling end to the title race between the Old Firm rivals.

"We just pushed forward and didn't have much to lose today," he said.

"I'm sure the other teams will do the same, whether it be at Ibrox or Parkhead or at their own home ground.

"The other teams - Motherwell, Dundee United and Hibs - are all battling for something so it's wonderful for the neutral supporters."

Celtic manager Gordon Strachan admits he feared a smash and grab after his side failed to kill off the game.

He said: "The second goal was the big one and we had opportunities to finish it off.

"As long as it's 1-0, and with the kind of season we have been having, it was a possibility. But we handled it not too bad.

"It's about goals and the ability to score goals. We had enough chances to do that and we couldn't take those chances.

"But it was fine. Because basically all football is about in this town is winning. Trust me, I know that."

Asked if Diamond's disallowed goal at the end was a relief, he added: "Yes, I was quite pleased with that. You never knew with the decisions today what was going to go for you or against you.

"Anything could have happened out there today decision-wise."

Andreas Hinkel was withdrawn at half-time with a hamstring strain and Strachan said it was too soon to tell whether he - along with today's absentees Paul Hartley, Lee Naylor and Jan Vennegoor of Hesselink - will be fit for next week's Old Firm derby.