Georgios Samaras fired his second winner this week to send Celtic back to the top of the Clydesdale Bank Premier League. with a 1-0 victory over Hearts.
The Greek forward drilled home in the 34th minute following a Kris Commons through-ball and Celtic comfortably saw out the win even if their performance failed to match the spark of their maiden Champions League away win against Spartak Moscow.
Callum Paterson had missed a great chance to give Hearts the lead before Celtic lifted their game with Commons again at the heart of their best play.
Celtic were without Scott Brown, who continues to battle a hip problem, and lost his Scotland team-mate Charlie Mulgrew in the first half following an early collision with Hearts goalkeeper Jamie MacDonald, who was carried off with a bad head knock.
There were immediate signals he would be unable to continue after he bravely attacked Emilio Izaguirre's cross to punch the ball away from a crowd of players. The goalkeeper was taken off wearing a neck brace to warm applause from around the stadium with Peter Enckelman taking his place in the 13th minute.
Celtic initially found it difficult to break down Hearts' solid formation and Paterson should have scored in the 25th minute after Andrew Driver slid in to dispossess Kelvin Wilson as the Celtic defender tried to shepherd the ball behind for a goal kick. Driver laid the ball back but Paterson fired wide from 12 yards.
Celtic responded when Samaras met a Commons cross with a controlled first-time volley which hit the outside of the post.
Mulgrew left the field, apparently concussed, and handed the captain's armband to Samaras, who took just two minutes to embrace his new-found responsibility with the opener. Commons was the provider with a pass with the outside of the foot into the left channel and the Greece striker ran on to it and fired a left-foot shot through the legs of Enckelman.
In the second half Commons fired just over the top corner after good skill in the box and Enckelman pushed Izaguirre's strike past his near post after the left-back had nutmegged Ryan McGowan.
Samaras headed over Commons' cross from six yards and Enckelman saved from James Forrest as the winger stumbled on to a left-footed shot before palming away a Commons shot in unorthodox fashion.