Gillingham stun high-flying Leeds with a sensational display in the sunshine at krbs Priestfield
With Josh Gowling serving a two-match ban after his red card against Brighton, Mark Bentley earned a recall at centre-half while Oli and Howe got the nod in attack.
The home side had a nightmare opening to the match, losing skipper Barry Fuller moments after kick-off when the right-back collided with Darren Dennehy and appeared to break his nose. Youngster Jack Payne, more used to playing in centre midfield, was brought on to deputise.
Four minutes later, Priestfield exploded as Adam Miller gave the Gills a shock lead, John Nutter's throw-on was flicked on by Richard Naylor, giving Miller a free header into the top right corner of Higgs net.
Leeds response was swift, Becchio teeing up Gradel to shoot from the edge of the box but Alan Julian was out quickly to narrow the angle and make an important save. Gillingham weren't about to roll over thoughand could have doubled their lead when Howe struck the post with a low drive from just inside the box.
Things got even better for Gillingham in the 29th minute as Mark Bentley rose to meet Adam Miller's left wing free-kick and headed emphatically beyond Higgs to put the home side two goals up.
Three minutes later the Gills surreal afternoon got better still. Another Miller free-kick was only cleared as far as Jack Payne, he curled a cross back in to the area and Leeds captain Richard Naylor sliced his clearance off the head of Neill Collins and into the net for Gillingham's third.
Leeds did pull one back, moments before the half-time break, Lucian Becchio collecting the ball inside the box and spinning on a sixpence before placing his finish beyond Julian and into the far corner.
Leeds made a strong start to the second half but were matched by their hosts for spirit, prompting Manager Simon Grayson to bring on top scorer Jermaine Beckford and Ben Parker in a bid to break Gillingham's resistance.
62 minutes had passed before the visitors carved out another opening, Neil Kilkenny blazing over the bar from the edge of the box. Ben Parker followed suit soon after, this time dragging a fierce drive wide of Julian's left-hand upright.
Simeon Jackson entered the fray with 20 minutes to go as Stimson sought to relieve some of the pressure on his back four. The Gills star striker caught a sight of goal in the 80th minute but under pressure from Naylor could only roll his finish into the arms of Shane Higgs.
Three minutes later a free-kick from Kilkenny was cleared to Max Gradel just outside the box but the forward could only volley harmlessly over the bar. Then on the 85th minute referee Wiley gave Leeds a lifeline by awarding a penalty for a foul on Beckford. The Leeds striker dusted himself down and drove his spot-kick into the bottom left corner for 3-2.
Despite an additional four minutes added time Gillingham ground out the time to record a momentous victory.
Attendance: 9649 (Leeds 2,241)
Gillingham: Alan Julian, Barry Fuller (Jack Payne 3), John Nutter, Mark Bentley, Darren Dennehy, Andy Barcham, Adam Miller, Danny Jackman, Dennis Oli, Curtis Weston (Simeon Jackson 72), Rene Howe
Subs not used: Simon Royce, Kevin Maher, Chris Dickson, Tom Wynter, Connor Essam.
Leeds United: Shane Higgs, Michael Doyle, Richard Naylor , Neil Kilkenny, Luciano Becchio (Sanchez Watt 77), Johnathan Howson, Andy Hughes (Ben Parker 55), Robert Snodgrass (Jermaine Beckford 55), Leigh
Bromby, Max Gradel, Neil Collins
Subs not used: Casper Ankergren, Mike Grella, Gary McSheffrey, Shane Lowry.