A last-minute goal from defender Gary Smith gave ten-man Hibs victory over bottom club Dundee United.
Dean Shiels blasted Hibs in front from ten yards on 35 minutes but Jim McIntyre headed United level from a corner.
Garry O’Connor finished off a swift counter to put Hibs ahead again but Jason Scotland shot the visitors back into the game on 77 minutes.
Hibs skipper Ian Murray was sent off before Smith headed in the winner after a frantic penalty box scramble.
The Tannadice side managed the first shot on goal when McIntyre spun cleverly in the box and arched a shot straight at goalkeeper Simon Brown.
Despite some excellent midfield prompting from the busy Scott Brown, Hibs struggled to find any attacking rhythm in the early stages.
And the visitors came close to opening the scoring when Barry Robson’s cross was headed towards goal by McIntyre, only for Gary Caldwell to clear off the line.
Hibs had a chance when Shiels robbed Mark Wilson with a fine tackle which sent the ball spinning to Riordan, but the striker pulled a weak shot wide.
Hibs should have gone ahead when Brown’s pass set Garry O’Connor through on goal but the striker fired straight at the legs of United keeper Tony Bullock.
The home side were looking more menacing and Riordan’s fierce shot struck the post just a few minutes before they took the lead.
With 35 minutes played, Riordan did exceptionally well to pull the ball back from the by-line and his cross fell into the path of Shiels, who fired into the top of the net from 10 yards out.
Soon after, Hibs hit the woodwork again when a great curling shot from Stephen Glass sailed beyond Bullock but bounced to safety off the post. Hibs continued to look strong after the interval but United were back in the game when Wilson’s inswinging corner was headed home by McIntyre.
On 68 minutes Hibs midfielder Kevin Thomson made his long-awaited return from his cruciate ligament injury when he replaced Steven Fletcher.
And a minute later Hibs were celebrating when O’Connor dismissed the challenge of Garry Kenneth and lashed the ball home from a tight angle.
Substitute Scotland made an immediate impact by bustling past Caldwell and side-footing home United’s second equaliser from close range.
With seven minutes left Hibs captain Murray was sent off after referee John Underhill was alerted by one of his assistants.
But Hibs were not to be denied and Smith nodded home from four yards out to hand the home side the points in an incredible finale.
Hibs: Simon Brown, Smith, Caldwell, Murray, Murphy, Fletcher, Scott Brown, Glass, Shiels, O’Connor, Riordan.