Last Updated: Mon, 01 Apr 2013 20:49
Jake Buxton's 87th-minute header earned Derby a ninth successive win against a Leeds side looking anxiously over their shoulders.
Buxton's bundled effort came just seconds after the Rams were denied a penalty when Michael Jacobs was brought down in the box.
Prior to that Paul Coutts had netted the rebound from a missed Conor Sammon spot kick, which came just six minutes after substitute Ross McCormack's 67th-minute opener for United.
As a result of the win Derby remain comfortable in mid-table and, although Leeds are one of the other sides in and around them, they are starting to slide. This was their fifth game without a win and their unpopular manager Neil Warnock was serenaded with a number of expletive-laden chants throughout.
The lively finish to the game belied a dismal opening hour which offered little and showed just why neither of these sides have challenged the pacesetters this season. Sammon received no backing as he appealed for an early penalty - he looked to have slipped as Jason Pearce approached.
Leeds' teenage debutant Chris Dawson helped tee up former Derby man Paul Green who cracked the bar from the edge of the box, while at the other end Paddy Kenny was quick off his line to close down Sammon after he beat Pearce to a neat through-ball from Chris Martin.
Derby, improving more than their hosts, thought they had taken the lead with 63 minutes gone, as Lee Peltier put a Martin cross through his own goal, but Sammon, no more than an inch ahead of him, was called offside.
Leeds brought McCormack off the bench as a bid to liven things up and the move reaped immediate dividends as the Scot opened the scoring with his first touch. McCormack, who, from his position just outside the area, cracked a first-time curler beyond Frank Fielding and into the top corner.
Leeds' advantage would last just six minutes, though, as Derby got themselves deservedly back on level terms. Pearce was found short of pace and he bundled Martin to the floor, leaving Roger East with a simple decision to make. Sammon proceeded to roll the penalty onto the post, although fortunately for him Coutts was on hand to convert the rebound.
A second penalty should have followed as Aidy White brought down Jacobs six yards inside the area - East awarding a free-kick - but, after Ben Davies' effort was saved by Kenny, the winger's subsequent corner was nodded in by Buxton.
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