Celtic manager Gordon Strachan hailed his team's "fantastic energy" after an assertive second-half display overcame a difficult challenge from Aberdeen.

Scott McDonald took his tally for the Hoops to 50 goals with a late double to hand them a 3-1 victory at Pittodrie and keep them on course for their fourth successive Clydesdale Bank Premier League title.

Strachan was critical of his players at the interval but he was delighted with their response and said: "We stuck at it and reorganised at half-time and got better and better and better. Their energy was absolutely fantastic and they made a lot of good chances."

He added: "There was high energy and purposeful football from Aberdeen in the first half.

"We had a few chances but we were a bit lax with our tackling, heading and a bit indisciplined in giving free-kicks away."

Aberdeen manager Jimmy Calderwood also felt Celtic's energy was the key to their victory, although he rued his side's missed chances and Dougie McDonald's decision to penalise Richard Foster for a challenge on Aiden McGeady before Celtic's equaliser.

"Celtic got a massive lift, their big players started playing and I thought Scott McDonald was brilliant the whole game," Calderwood said.

"Nakamura was fantastic. He was doubling up on (Sone) Aluko. Outside his football quality, his work rate is unbelievable.

"I know, when you look at the ProZone, the yards that he runs. I told the young lads to learn from him.

"He's a great player and he's also a great professional."