Sasa Papac came to Rangers' rescue with a late winner against St Johnstone to send the Scottish champions to the summit of the Premier League.
The full-back picked the ideal time to net his first goal of the season when he grabbed the decider at McDiarmid Park after Kris Boyd had cancelled out Collin Samuel's opener.
Celtic surrendered their lead at the top of the Premier League to Old Firm rivals Rangers after failing to break down Motherwell at Parkhead.
Niall McGinn headed wide just before the break with the best chance of the first half but that only proceeded a catalogue of missed chances in the second period which led to the Hoops fans booing and jeering at the final whistle.
Craig Dargo scored one and set up another as St Mirren came from behind to win 2-1 and keep Falkirk bottom of the Premier League. The former Inverness striker hooked home a 67th-minute equaliser and his cross soon led to Billy Mehmet's eighth goal of the season.
Substitute Tom Brighton then killed off Falkirk, who had taken the lead in the 55th minute when Brian McLean made sure Alex MacDonald's header crossed the line.
Hibernian striker Abdessalam Benjelloun scored a dramatic late penalty to give the hosts a well-deserved three points against a dogged Kilmarnock.
Just as it looked like the Rugby Park side might emerge with a share of the spoils after frustrating a dominant Hibs, Gavin Skelton was penalised for felling the Moroccan inside the area eight minutes from time.
Aberdeen and Hearts shared the points in an evenly-matched Premier League encounter at Pittodrie that ended 1-1.
Lee Miller put the home side in front three minutes before the interval, heading home Michael Paton's cross from close range. But Hearts levelled through prospective Scotland cap Andrew Driver after 63 minutes, the Oldham-born winger coolly slotting home substitute Christian Nade's pass.
Dundee United snatched a stoppage-time equaliser against Hamilton, as the teams drew 1-1 at Tannadice.
Mickael Antoine-Curier looked to have scored a hotly-disputed winner for the visitors, the on-loan Dundee striker's 65th-minute goal infuriating the home players and fans, who were adamant he was offside.
United twice hit the woodwork late on before Garry Kenneth's late header spared Craig Levein's men back-to-back home defeats.