Kilmarnock 2-2 Celtic
Kilmarnock claimed their first Scottish Premiership point of the season as Celtic were denied a third straight victory.
Leigh Griffiths tucked away the visitors' opener within two minutes, but Josh Magennis fired Killie level before the break.
Nir Bitton's stunning 25-yard effort looked to have given Celtic the win.
But Emilio Izaguirre fouled Greg Kiltie in the box and Kallum Higginbotham chipped home the resulting penalty.
The stylish finish displayed a confidence far from evident in the opening stages, during which the hosts could have been several goals behind.
Griffiths outstripped his markers to latch on to Commons' quickly-taken free-kick from near halfway to roll the ball past the outrushing Jamie MacDonald.
Commons, Tom Rogic, Griffiths and James Forrest all tested MacDonald from varying distances as the onslaught continued.
However, Celtic lost Commons to injury with Gary Mackay-Steven coming on and their attacking became less fluid.
Magennis, who had been rather isolated in attack, was presented with an excellent chance when he raced beyond the Celtic defence to meet Rory McKenzie's pass.
The visitors waited in vain for an offside flag and the Northern Irishman held off Virgil van Dijk only to skew the ball high and wide.
However, the opportunity galvanised Gary Locke's men and Lee Ashcroft's header from a Steven Smith free-kick was well saved by the feet of goalkeeper Craig Gordon.
Defender Ashcroft, who had not been moving easily, subsequently made way for O'Hara.
Rogic was guilty of a miss more glaring than Magennis's when Celtic threatened at a free-kick. The Australian headed against the post then had a shot blocked by MacDonald and, with the goal at his mercy, he volleyed his third attempt over.
And, almost straight away, Killie were level as Magennis got across Efe Ambrose to sweep Darryl Westlake's low centre past Gordon.
Celtic opened the second half with the same attacking intent as they had the first and Griffiths should have buried a chance created by Forrest's cross from the left.
Bitton, after seeing a bouncing shot held by MacDonald, restored Celtic's lead when he belted the ball beyond the goalkeeper's despairing dive.
Keen not to be pegged back a second time, Celtic pressed hard for a third and MacDonald stretched to touch away two Griffiths efforts and the striker was narrowly off target with an acrobatic volley.
Long-range efforts were the order of the day and McKenzie raised home hopes with a dipping shot that Gordon tipped over.
The Celtic stopper also blocked Aaron Splaine's free-kick and a header from O'Hara.
Celtic had the ball in the net a third time when Forrest's replacement, Charlie Mulgrew, followed in on a saved Griffiths shot, but the offside flag was raised.
Kiltie had troubled the visitors all evening and, when he was bundled over by Izaguirre, Higginbotham deceived Gordon with a delicately struck spot-kick - his first goal for Kilmarnock and a welcome one for the hosts.
- 18AshcroftSubstituted forO'Haraat 42'minutes
- 23KiltieSubstituted forMcLeanat 90+2'minutes
- 8RobinsonSubstituted forSplaineat 66'minutes
- 5van Dijk
- 6BittonSubstituted forMcGregorat 85'minutes
- 15CommonsSubstituted forMackay-Stevenat 29'minutes
- 49ForrestSubstituted forMulgrewat 60'minutes
- Crawford Allan
- Shots on Target