Michael Ihiekwe, Michael Smith and Ryan Giles scored in the final 15 minutes as Rotherham beat Derby County to move to within two points of escaping the Championship relegation zone.
Moments after Rams substitute Lee Gregory headed wastefully wide on his debut, Ihiekwe steered in the opener at the back post from a deep free-kick.
Smith then turned in the second from Matt Crooks’ lovely right-wing cross after a swift counter-attack.
A delightful solo goal from substitute Giles rounded off a fine win and secured a second league success for the Millers against Wayne Rooney’s side this season.
Derby had won their previous three games and could have gone six points clear of the bottom three but capitulated after falling behind and are now just two points above the Millers – who have two games in hand – in 20th place.
The hastily rearranged fixture – played just 24 hours after the game was postponed because of a waterlogged pitch – produced very little action in the first half.
Colin Kazim-Richards and Martyn Waghorn were prominent figures in a lively Derby start, with the latter going close to opening the scoring when he diverted an effort just over from close range.
The hosts struggled to unpick an ever-improving Rams defence which had not conceded a goal in three games since last being breached in Rotherham’s 1-0 victory at Pride Park on 16 January.
But the hosts offered a threat from set-pieces, Clark Robertson heading over their first noteworthy chance at the near post from a left-wing corner, while fellow Scot Jamie Lindsay should have scored when played in down the right only to shoot narrowly wide.
The pattern continued after the break with Derby looking more fluid in attack and defensively secure in open play, but vulnerable at free-kicks and corners.
Max Bird saw a decent low effort saved by home keeper Viktor Johansson after good work by Kazim-Richards before Gregory squandered their best opportunity from Nathan Byrne’s cross.
Ihiekwe’s opener from a simple diagonal ball into the box that was flicked on by Smith saw Derby lose their shape, and Rotherham took full advantage.
Smith’s sixth goal in eight games made it 2-0 after 81 minutes before Giles scored the best goal of the evening, winning possession on the left and driving at the defence before shooting low into the far corner.
Derby County boss Wayne Rooney:
“We controlled large portions of the game and we always knew set-pieces would be important.
“The first goal was vital. I feel if we score that then we go and win the game. Lee had a great opportunity and should score.
“They hit us on the break for the second goal and the game was over after that.”
Rotherham boss Paul Warne:
“We didn’t start as well as I would have liked. I thought we showed them a bit too much respect.
“In the end I thought we could have scored more. It was an edgy game but to come away with a clean sheet and three goals, we’re really pleased.
“The players have been magnificent, even in defeats. Fortunately tonight the ball bounced for us kindly in the six-yard box and we took our chances.
“We have had three wins out of five. With this amount of games left, we have our destiny in our own hands.”
- 22OlosundeSubstituted forGilesat 69′minutes
- 16LindsaySubstituted forMacDonaldat 84′minutes
- 26BarlaserSubstituted forWingat 68′minutes
- 8WilesBooked at 57minsSubstituted forMacDonaldat 90+2′minutes
- 25CrooksBooked at 83mins
- 24SmithSubstituted forLadapoat 84′minutes
- 8BirdBooked at 65mins
- 4ShinnieBooked at 59minsSubstituted forBaningimeat 87′minutes
- 9WaghornSubstituted forGregoryat 72′minutes
- 7JozwiakSubstituted forRobertsat 72′minutes
- 13Kazim-RichardsSubstituted forSibleyat 87′minutesBooked at 90mins
Match ends, Rotherham United 3, Derby County 0.
Second Half ends, Rotherham United 3, Derby County 0.
Louie Sibley (Derby County) is shown the yellow card for a bad foul.
Foul by Louie Sibley (Derby County).
Matt Crooks (Rotherham United) wins a free kick in the attacking half.
Foul by Louie Sibley (Derby County).
Lewis Wing (Rotherham United) wins a free kick in the defensive half.
Substitution, Rotherham United. Shaun MacDonald replaces Ben Wiles.
Offside, Rotherham United. Ryan Giles tries a through ball, but Freddie Ladapo is caught offside.
Corner, Derby County. Conceded by Clark Robertson.
Beni Baningime (Derby County) wins a free kick in the defensive half.
Foul by Wes Harding (Rotherham United).
Corner, Derby County. Conceded by Angus MacDonald.
Attempt blocked. Jason Knight (Derby County) right footed shot from outside the box is blocked.
Goal! Rotherham United 3, Derby County 0. Ryan Giles (Rotherham United) left footed shot from the left side of the box to the bottom right corner.
Substitution, Derby County. Louie Sibley replaces Colin Kazim-Richards.
Substitution, Derby County. Beni Baningime replaces Graeme Shinnie.
Lee Gregory (Derby County) wins a free kick in the defensive half.
Foul by Lewis Wing (Rotherham United).
Attempt missed. Max Bird (Derby County) right footed shot from outside the box misses to the right following a set piece situation.