Mark Wilson's first goal of the season moved Doncaster a step closer to safety and ended Derby's run of four consecutive victories with a 2-1 win in their Coca-Cola Championship clash.
Wilson fired home the winner from 25 yards with 19 minutes remaining at the Keepmoat Stadium, a strike that should have been kept out by Rams keeper Stephen Bywater.
Robbie Savage looked to have put Nigel Clough's resurgent Rams on course for a fifth consecutive league win when he curled home a precise free-kick early in the second half, before Paul Heffernan responded with a clincal header six minutes later.
Doncaster stroked the ball around with the confidence of a side challenging for promotion, but it was Derby who came closest early on when Teale stung the palms of Neil Sullivan after 23 minutes.
Porter came close to opening his account when his measured header looked to be looping into the far corner of the net but rebounded off the bar.
The visitors were in front four minutes into the second half courtesy of a moment of class which had been missing in the first period.
After Hulse was brought down on the edge of the area, Savage curled a free-kick over the wall and into the corner of the net, giving Sullivan no chance.
But Doncaster responded positively to going behind and drew level six minutes later. Wilson was allowed too much time to line up a cross on the right flank and Derby paid the price as Heffernan rose to guide a header inside Bywater's left-hand post.
Rovers were in front 19 minutes from time courtesy of a mistake from Bywater. Derby failed to clear a corner from the left and Wilson found the bottom corner from 25 yards out with a right-foot strike that Bywater really should have got at least a hand to.
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