UNITED 1 (Gradel 89), ORIENT 0
United: Ankergen, Bromby, Michalik, Kisnorbo, Hughes (White 47), Howson (Grella 81), Doyle, Kilkenny, Snodgrass, Beckford, Vokes (Gradel 62). Subs: Martin, Prutton, Robinson, Somma.
Orient: Jones, Chorley, Mkandawire, Purches, Thornton, Summerfield (Jarvis 90), Smith, Daniels, Townsend, Chambers, McGleish (Scowcroft 60). Subs: Morris, Ashworth, Melligan, Demetriou, Cave-Brown.
Referee: D Foster
Att: 19,744
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Simon Grayson named an unchanged side as his Leeds United side looked to strengthen the grip on League One.
United went into the game on the back of three straight league victories, having scored 11 goals and conceded none since the 2-1 defeat at Millwall last month.
It was the visitors who had the first attempt of the night when Andros Townsend lifted a shot well over the bar, following a free-kick, but it was Leeds who enjoyed the early possession, playing some good football.
But the visitors carved out a decent a chance on 12 minutes when Sean Thornton screwed a shot wide after some good build-up play around the Leeds box. Townsend also tried his luck again with a shot from distance which Casper Ankergren smothered at the second attempt.
And Patrick Kisnorbo was called upon to make a good challenge as the visitors played with a spring in their step.
Leeds struggled to find any real fluidity during the opening 20 minutes, while Orient played with one man up front and looked to counter-attack.
United did have an opportunity before the half-hour when a Robert Snodgrass free-kick was blocked by the defensive wall, following a foul on Neil Kilkenny on the edge of the box. Kilkenny also lifted a shot over the top as the visitors struggled to clear their lines.
But it took an Andrew Hughes block to deny Scott McGleish at the second attempt after good work by Adam Chambers down the Orient right.
Leeds responded immediately, but the ball didn't quite drop for Sam Vokes after a Jermaine Beckford nod-on and he lifted his shot over the bar.
Orient continued to play, though, and Thornton tested Ankergren again on 36 minutes with another good strike.
As the game ebbed towards half-time Micky Doyle looked to pick out an advancing Beckford with an incisive pass, but good defending denied the United striker. Moments later, Orient goalkeeper Jamie Jones proved equal to a Jonny Howson effort after some neat passing play.
Leeds emerged for the second half quite a few minutes before the visitors, and just 90 seconds into the second period, Adie White was introduced in place of Andrew Hughes.
White's first involvement was to release Snodgrass down the left, who twisted and turned inside the box before seeing his cross blocked.
Leeds certainly started more positive, although rather like the game against Charlton at the start of October, a swirling wind at pitch level was making conditions increasingly difficult.
United were beginning to look more of a threat and Vokes could only watch as his low cross fizzed across the face of goal, just too far in front of an advancing Beckford.
On 62 minutes, Grayson made his first change of the night introducing Max Gradel in place of Vokes. And the loan man showed some immediate trickery to delivery a cross into the box which Orient cleared at the second attempt.
Orient defender Ben Chorley was also called upon to get a decisive touch on a Gradel free-kick, ahead of Kisnorbo, and his looping header fell into the arms of Jones.
And United came within a whisker of taking the lead on 72 minutes when, with his back to goal, Gradel lifted a shot over the top after great work by Beckford and Snodgrass.
It was a proving to be a frustrating evening, but Orient were on the back foot, as Leeds looked to force an opening.
United had two shouts for a penalty waved away, first for a handball and then when Beckford went down under pressure from a visiting defender, but the visitors again scrambled their lines clear and looked to break quickly.
You could sense an opening was maybe coming as Leeds looked to step it up, and Snodgrass had an effort cleared after good work by Howson on the right. Leeds had gone three up front with Gradel and Snodgrass playing alongside Beckford, and there was another penalty shout when Snodgrass felt he was felled by Chambers.
As the game entered the final 10 minutes, Grayson threw on Mike Grella in place of Howson and Leeds went with an attacking four in a bid to win the game.
Gradel switched to the right and he immediately forced Jones into making the best save of the night when he palmed over his shot. Grella also had a shot blocked after cutting inside from the flank and Leeds were certainly applying the pressure.
United threw nine players into the box when Kisnorbo launched a free-kick from the Leeds half as a further sign if intent, but still the breakthrough wouldn't come.
But, just as it looked like being an evening of frustrating, Gradel displayed some real magic inside the box, shaping to shoot before firing the ball beyond Jones.
The goal was no more than Leeds deserved, despite Orient's resilience, and Elland Road erupted as the loan man was mobbed by his jubilant team-mates.
Rather that provoke any fear, the signal for four minutes of added time simply provided belief of a further goal and Snodgrass flashed a shot into the side-netting as the near 20,000 crowd roared Leeds towards victory.
And, victory it was as United's unbeaten run at home stretched to 20 games and the lead at the top was protected and even extended over some of the club's jostling in the Play-Off spots.
