Inverness Caley Thistle came from two goals behind to record an amazing victory over Scottish champions Celtic.
Two headed finishes within a matter of seconds from Jan Vennegoor of Hesselink appeared to put Celtic in control.
But John Rankin powered home a penalty and, after the break, David Proctor headed a second and Don Cowie slotted in a third to rock the SPL leaders.
Proctor was sent off after 67 minutes for a foul on Scott McDonald, but Celtic could not find an equaliser.
Caley Thistle's first-ever league win over Celtic made sure that Rangers remain only two points behind their Glasgow rivals at the top of the table with two games in hand.
Both sides had stuck with the line-ups that led them to victory in their last respective fixtures.
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But it was Celtic who created the first chances, Phil McGuire clearing a Scott Brown effort off the line and goalkeeper Michael Fraser turning wide a McDonald shot on the turn.
Inverness survived the early danger, but a pair of two-minute spells with contrasting fortunes appeared to swing the game decisively in Celtic's favour.
Ian Black's drive deflected into Marius Niculae's path and the Romanian's volley looped past the far post off the hand of former Caley Thistle goalkeeper Mark Brown.
Black then fired a powerful effort from 25 yards straight into his former team-mate's arms.
Celtic responded immediately to the threat by taking the lead.
After the visitors were awarded a disputed free-kick, Paul Hartley whipped in a cross that was headed down into the corner of the net by Vennegoor of Hesselink from 10 yards out.
Less than 80 seconds later, the Dutch striker struck again from a similar distance with a glancing finish to Aiden McGeady's curling drive.
Inverness refused to buckle and were back in the match just before the break.
Steven Pressley stumbled into Niculae in a race for a Rankin through ball, with the striker slicing his effort wide.
The Celtic defender survived without even a yellow card, but Rankin powered the resulting penalty kick under Brown's body.
Inverness looked inspired after the break, although Vennegoor of Hesselink came close to his hat-trick when his 18-yard drive bounced clear off the face of the post.
Caley Thistle survived to rock the reigning champions with a 56th-minute equaliser.
Proctor met Cowie's corner to head powerfully home from 12 yards.
Celtic thought they had restored the lead, but McDonald was caught marginally offside when finishing from eight yards.
Inverness raced up the other end to move ahead after 60 minutes, when Stephen McManus failed to clear Richard Hastings' high ball and Cowie slid in to fire home.
The home side were reduced to 10 men seven minutes later when Proctor barged into the back of McDonald after the striker raced clear.
McGeady's free-kick from the edge of the box curled just wide.
And Fraser pulled off a breathtaking save to claw a goalbound McManus header off the line to ensure a famous victory.
Inverness CT: Fraser, Proctor, McGuire, Munro, Hastings, Cowie (Wilson 86), Black, Duncan, Rankin, McBain (Tokely 69), Niculae (Bayne 81).
Subs Not Used: Malkowski, McAllister, Vigurs, Duff.
Sent Off: Proctor (68). Booked: Hastings.
Goals: Rankin 42 pen, Proctor 57, Cowie 61.
Celtic: Mark Brown, Caldwell, Pressley (Riordan 77), McManus, Conroy, Scott Brown, Hartley, Donati, McGeady, Vennegoor of Hesselink, McDonald (Killen 81).
Subs Not Used: McGovern, Sno, O'Dea, Jarosik, Balde.
Booked: McGeady.
Goals: Vennegoor of Hesselink 24, 26.
Att: 7,004
Ref: A Freeland
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