Aberdeen moved top of the Premiership as champions Celtic needed a late Callum McGregor strike to salvage a point and preserve their long unbeaten run.
The Dons took advantage of Brendan Rodgers' side dropping points after a thrilling 4-3 win at Partick Thistle and were on their way after just five minutes through Ryan Christie, only for Chris Erskine to equalise moments later.
Alan Archibald's side then took the lead in the 13th minute when Kris Doolan stabbed home a Blair Spittal corner but Kenny McLean made it 2-2 from the penalty spot three minutes before half-time after Christie had been pushed in the area by Stuart Bannigan.
Scott Wright briefly gave Aberdeen the lead at the start of the second half with a fine strike but, within two minutes, Niall Keown headed in Spittal's corner for Thistle.
Adam Rooney secured the win for the Dons, though, by heading home Christie's cross with six minutes remaining before Keown was sent off for a second bookable offence.
Celtic had to settle for a 1-1 draw but might have taken nothing against fellow early pacesetters St Johnstone had McGregor not stepped off the bench to cancel out Steven MacLean's opener.
MacLean took advantage of a poor clearance from Craig Gordon to put the visitors ahead six minutes before half-time - scoring his 50th goal for Saints in the process.
Jonny Hayes fired wide and Alan Mannus saved twice in quick succession from Leigh Griffiths and Stuart Armstrong as the hosts piled on the pressure.
They were eventually rewarded when McGregor, a 61st-minute substitute, slotted the equaliser with 11 minutes remaining.
Scott Sinclair and Mikael Lustig both hit the woodwork for Celtic but both sides were forced to relinquish their 100 per cent starts.
Ali Crawford's late penalty helped Hamilton fight back to claim a 2-2 draw against Kilmarnock at Rugby Park.
Killie had lost all three of the games in the Premiership but an own goal from Louis Longridge and Lee Erwin's second-half lob seemingly set them on their way to victory.
However, Giannis Skondras fired home for Accies in the 71st minute and Crawford converted from the spot with two minutes left to secure a share of the spoils.
Louis Moult's fine first-half strike completed Motherwell's comeback as they beat Hearts 2-1 at Fir Park.
Kyle Lafferty handed Hearts the lead on the half-hour mark with a low 25-yard effort but Ryan Bowman levelled with a diving header for Well seven minutes later.
The hosts then took the lead three minutes before half-time through Moult, who curled superbly into the top corner from 20 yards.