Sheffield United enjoyed a 3-1 victory over Derby County to end the Rams' three-match winning streak.
The Blades led 2-0 at half-time, due to a goal from captain Billy Sharp and a Johnny Russell own goal.
A late Craig Bryson header set up a nervy finish for the Yorkshire side but Sharp capped off the Blades' win.
The Blades took the lead after a bright start, when Derby keeper Scott Carson's attempted pass fell straight to Sharp and he struck low into the bottom left corner in only the fourth minute.
Derby instantly pushed for an equaliser, Russell forcing a tackle from the United defence after dispossessing Paul Coutts and running towards goal.
United had a chance to extend their lead as Coutts' low effort from outside the box went wide of the left-hand post.
Continuing their push for a second, Sharp had a shot blocked after neat build-up play inside the Derby penalty area.
Weimann then fired just over after receiving the ball to the right of the Blades' goal.
United defender Jack O'Connell was booked for stopping a counter-attack by bringing down Weimann as Derby looked to break clear.
Derby were then through on goal after another fast break, but a superb last-ditch tackle from John Fleck denied Matej Vydra as he looked likely to score.
After narrowly missing the United goal with a curling effort, Russell struck into his own net to double the Blades' lead six minutes from half-time as he badly misjudged an attempt to prevent a shot on goal.
Tom Huddlestone had Derby's first real chance of the second half, flashing an effort wide of the post after receiving the ball from a throw-in. Russell then tried to lob Blackman but the keeper collected.
And seconds later, Blades striker Caolan Lavery was replaced by Ched Evans after clashing heads with Marcus Olsson.
Derby sent on Tom Lawrence and Chris Martin in place of Russell and David Nugent but Lawrence was booked almost immediately after a bad foul.
Derby were denied a penalty, and minutes later a low cross from substitute Samir Carruthers flashed just past Sharp.
Johnson was booked for a foul on Carruthers, before Weimann was replaced by Craig Bryson.
Carruthers was forced off due to injury with 10 minutes to go and was replaced by John Lundstram.
Lawrence nearly scored his first goal for the Rams, narrowly missing the top corner, before Carson kept out a low effort from Sharp at the other end.
Bryson pulled a goal back for Derby in stoppage time, heading into the bottom corner.
But Sharp later tapped into an empty net, after Carson had pushed up, to secure the points for the Blades.