Match ends, Falkirk 3, Rangers 2.
Bob McHugh struck in stoppage time as Falkirk recovered from the loss of two early goals to stun Rangers.
Blair Alston found the top corner on 72 minutes and Myles Hippolyte rounded the goalkeeper to level before McHugh turned in a neat, near-post finish.
Rangers looked on course for a comfortable victory when Kenny Miller and Barrie McKay applied close-range finishes inside nine minutes.
But the Championship leaders let their lead at the top slip to 11 points.
It was just a third league defeat of the season for Rangers, who will guarantee the title with four wins from their remaining seven games.
But Falkirk boast the same number of losses and a remarkable comeback also takes them six points clear of Hibernian, although they have played three more games than the team in third place.
Rangers had gone 15 matches unbeaten since losing another thriller to Falkirk in December and Mark Warburton's men could have been out of sight after a dominant first-half display.
Having had a strike incorrectly disallowed for offside, James Tavernier drilled in a cross for Miller to tap in the opener.
The huge travelling support were still celebrating when Rangers swaggered forward and fired in a second, with Lee Wallace setting up McKay.

Miller and McKay threatened again, while Wallace and Halliday had shots well saved by Danny Rogers before the interval.
Rangers started the second half with the same drive, with Miller and Halliday going close to extending their lead.
But the home side's desire was never in question and they began to cause problems for the Rangers defence as Luke Leahy, Will Vaulks and substitute Hippolyte had shots repelled by Wes Foderingham.
The Rangers keeper was also tested by a fierce Alston shot in the first half but had no chance when the Bairns midfielder expertly lashed the ball on the half volley into the top corner of the net.
Soon after, the increasingly lively Hippolyte found space on the left, skipped past Foderingham and blasted the ball beyond two covering defenders.
The home fans behind the goal rose and roared as one and in near disbelief as Hippolyte back-flipped away in delight.
And just as they were preparing to celebrate an unlikely point, McHugh handed them the victory and added to the delirium.
Kevin O'Hara did well to create room for a cross on the left and when he drove the ball in low fellow substitute McHugh nicked in to steer the ball home from inside the six-yard box.
A bewildered Rangers had scarcely any time to respond and Falkirk held on to secure a vital three points in their push for promotion.
Line-ups
Falkirk
Formation 4-4-2
- 1Rogers
- 4Muirhead
- 5McCracken
- 44Watson
- 3Leahy
- 8Alston
- 6Vaulks
- 10SibbaldSubstituted forO'Haraat 74'minutes
- 7Taiwo
- 9BairdBooked at 76minsSubstituted forMcHughat 80'minutes
- 18MillerSubstituted forHippolyteat 50'minutesBooked at 64mins
Substitutes
- 17Smith
- 19McHugh
- 22Hippolyte
- 26McCann
- 28Mehmet
- 30O'Hara
- 33Gallacher
Rangers
Formation 4-3-3
- 25Foderingham
- 2Tavernier
- 4Kiernan
- 27Wilson
- 5Wallace
- 16Halliday
- 6Ball
- 23Holt
- 17KingSubstituted forO'Halloranat 68'minutes
- 9MillerSubstituted forClarkat 69'minutes
- 19McKaySubstituted forForresterat 60'minutes
Substitutes
- 1Bell
- 7Law
- 14Clark
- 15Forrester
- 22Shiels
- 29O'Halloran
- Referee:
- Kevin Clancy
- Attendance:
- 7,804
Match Stats
- Possession
- Home37%
- Away63%
- Shots
- Home14
- Away17
- Shots on Target
- Home9
- Away10
- Corners
- Home4
- Away13
- Fouls
- Home8
- Away5
Live Text
Post update
Full Time
Second Half ends, Falkirk 3, Rangers 2.
Post update
David McCracken (Falkirk) wins a free kick in the attacking half.
Post update
Foul by Danny Wilson (Rangers).
Post update
Corner, Rangers. Conceded by Myles Hippolyte.
Goal!
Goal! Falkirk 3, Rangers 2. Robert McHugh (Falkirk) right footed shot from very close range to the centre of the goal. Assisted by Kevin O'Hara.
Post update
Corner, Falkirk. Conceded by James Tavernier.
Post update
Attempt blocked. Kevin O'Hara (Falkirk) right footed shot from the right side of the box is blocked.
Post update
Corner, Rangers. Conceded by David McCracken.
Post update
Corner, Rangers. Conceded by Aaron Muirhead.
Post update
Corner, Rangers. Conceded by Myles Hippolyte.
Post update
Corner, Rangers. Conceded by Aaron Muirhead.
Post update
Attempt blocked. Nicky Clark (Rangers) left footed shot from the centre of the box is blocked.
Post update
Attempt saved. Rob Kiernan (Rangers) header from the centre of the box is saved in the top centre of the goal.
Post update
Corner, Rangers. Conceded by Luke Leahy.
Post update
Attempt saved. Will Vaulks (Falkirk) right footed shot from outside the box is saved in the centre of the goal.
Post update
Myles Hippolyte (Falkirk) wins a free kick on the right wing.
Post update
Foul by Andy Halliday (Rangers).
Substitution
Substitution, Falkirk. Robert McHugh replaces John Baird.
Goal!
Goal! Falkirk 2, Rangers 2. Myles Hippolyte (Falkirk) left footed shot from the centre of the box to the centre of the goal.