Rangers' late fightback frustrates Celtic in Scottish title thriller
Trailing Celtic by just one point heading into the Ibrox showdown, Philippe Clement's side were rocked when Daizen Maeda gave the visitors the lead after just 21 seconds.
Rangers fell further behind in the 34th minute when Matt O'Riley converted a penalty.
But Rangers captain James Tavernier scored from the spot in the 55th minute to give the hosts renewed hope.
Abdallah Sima equalised in the 86th minute of a rollercoaster clash, only for Celtic's Adam Idah to net seconds later as Brendan Rodgers' men moved within touching distance of a priceless victory.
Rangers substitute Rabbi Matondo grabbed the leveller deep into stoppage time to leave the title battle on a knife edge.
Second-placed Rangers remain one point behind Celtic but have a game in hand against Dundee on Wednesday that would take them top with a victory.
They also still have to go to Celtic Park for one last Old Firm derby this term.
Less than a minute had elapsed before Celtic lit the fuse of an explosive encounter.
Joe Hart's long clearance went past a hesitant Tavernier, who tried to clear under pressure from Maeda but the ball rebounded off the Japan attacker and sped low past keeper Jack Butland from just inside the area.
Rangers were shaken by that freak goal and Butland had to make good saves to deny Maeda and Reo Hatate as Celtic pushed for a second goal that arrived after 30 minutes.
When referee John Beaton checked his pitchside monitor at the behest of VAR, he decided the ball had struck Rangers defender Connor Goldson on the elbow and awarded a penalty.
O'Riley dinked his spot-kick down the middle and Butland dived the wrong way as Celtic eyed a crucial win.
Rangers were booed off at half-time but Tavernier gave them a lifeline in the 55th minute.
After consulting the monitor again, Beaton pointed to the spot for a penalty following Alistair Johnston's foul on Fabio Silva and Tavernier blasted his kick high past Hart.
Rangers thought they were level two minutes later, only for Cyriel Dessers' close-range finish to be disallowed for Tom Lawrence's foul on Tomoki Iwata in the build-up.
With four minutes remaining, Sima collected a clearance inside the Celtic area and fired home via a deflection to the delight of the frenzied Ibrox crowd.
Just moments later, Idah took a pass from fellow Celtic substitute Paulo Bernardo and drilled low past Butland from the edge of the area.
But there was a sting in the tale in stoppage time as Matondo curled a superb strike past Hart into the top corner from 20 yards.
Passions boiled over at the final whistle as players from both sides briefly clashed in a row that sets the stage for a thrilling title denouement.