Celtic required a stoppage-time goal from Charlie Mulgrew to snatch a point against Dundee United when their unbeaten start to the Scottish Premiership looked in doubt.
The Hoops made a positive start and had plenty of chances to score before half time, despite the visitors enjoying plenty of early possession.
Mulgrew had the best of those opportunities when he met Emilio Izaguirre's cross but headed straight at Radoslaw Cierzniak.
They were made to pay when Nadir Ciftci played in Stuart Armstrong, who rifled a shot past Fraser Forster to give the Tangerines the lead just before half time.
Manager Neil Lennon increasingly threw caution to the wind as even defender Virgil van Dijk join in the attack as they went in search of a goal, but the hosts seemed like they would be frustrated.
Celtic's equaliser came in the second minute of stoppage time when Izaguirre again played in Mulgrew and this time the midfielder headed past Cierzniak to the relief of the Celtic Park faithful.
The result leaves Celtic five points clear of second-placed Inverness and still without a defeat in the league this season.
