Derby's impressive run under Steve McClaren continued to gather pace as they recorded seven consecutive league wins for the first time since 1995 by beating Doncaster 3-1 at the iPro Stadium.
Doncaster made them work for the victory that takes them into Christmas just two points outside the automatic promotion places, but their quality in front of goal was the difference between the teams.
Jamie Ward and Simon Dawkins scored either side of a missed penalty from Chris Martin and although Jake Buxton's own goal gave Doncaster hope, Craig Bryson sealed the points 13 minutes from time.
Derby had lost only once since McClaren became head coach in October so they hardly needed the seasonal generosity Doncaster's defence offered in the 13th minute.
Luke McCullough's failure to deal with a bouncing ball on the edge of his area allowed Chris Martin to pounce and play in Ward who rolled the ball past a furious Ross Turnbull from eight yards.
It was awful defending but Doncaster responded by forcing Derby back and in the 20th minute Richie Wellens hit a swerving shot from just outside the box that Lee Grant could only push out.
Former Derby striker Theo Robinson had a shot deflected over two minutes later and McClaren's team was forced to make a change in defence in the 25th minute when skipper Richard Keogh was replaced by Michael Keane.
But it was Derby who should have scored again when McCullough barged over Martin after Bryson's pass opened up Doncaster but Turnbull plunged to his right to save Martin's penalty.
Doncaster had played some neat passing football in the first half without seriously threatening Grant's goal but they had two chances to equalise at the start of the second.
Robinson shot into the side netting after escaping down the right in the 48th minute and he used his strength to muscle his way through a minute later only to shoot against the body of the advancing Grant.
Those misses came back to haunt the visitors in the 50th minute when Derby increased their lead.
Dawkins picked up the ball just outside the centre circle and ran at a retreating defence before firing low past Turnbull from just inside the area.
Derby now looked dangerous every time they went forward but after two crosses flashed across the face of the visitors goal and a Ward shot grazed a post, Doncaster got back in the game when Buxton headed a cross into his own net under pressure in the 64th minute.
Now it was Derby's turn to look jittery but they restored their two goal cushion in the 77th minute when a clever pass by Martin sent Bryson into the area and the midfielder placed his shot inside Turnbull's left-hand post from 12 yards.