Aberdeen came from behind three times against Celtic in an eight-goal thriller at Pittodrie, hindering the Hoops' League title hopes.
The first half ended level after goals from Diomansy Kamara and Marc-Antoine Fortuné had been cancelled out by Michael Paton and Darren Mackie, but the Parkhead side went two clear with goals from Robbie Keane and Aiden McGeady and it looked like the Hoops had sealed all the points.
However, there was more drama to come. Dons striker Steve MacLean reduced the deficit from the spot after Edson Braafheid had handled and MacLean then grabbed an 88th minute equaliser.
There was more woe for Celtic as the defender Darren O'Dea was sent off in the final stages for his second yellow card following a foul on Gary McDonald.
With Rangers playing Hibernian at Ibrox today, the advantage seems to have swung towards the Govan men who can restore their 10-point advantage.
The Celtic manager, Tony Mowbray, looked downbeat afterwards. "It is disappointing to lose the lead three times," he said. "The game is never over but it should have been. At 4-2 their goalkeeper made two great saves and it looked like the flow was going our way but we gave them a lifeline by conceding a penalty kick which was unexplainable."
The Aberdeen manager, Mark McGhee, had been involved in some controversy before the game but, contrary to speculation, did not field a weakened team ahead of Tuesday's Scottish Cup fifth-round replay against Raith Rovers.
"It was scandalous," the former Celtic and Aberdeen striker said. "The people who wrote that disappointed me because they questioned my professional integrity."
McGhee believed his side could still recover even when they went two down in the second half. "We could have done better defensively but even at 4-2 I still thought we could get back in the game," he said. "I felt if we could get a goal back quick enough then we could get something from the game."