Referee Michael Salisbury sent off Derby's Scott Malone and awarded Reading a penalty for his challenge on Yakou Meite
Charlie Adam netted his first goal in just under two years as Reading cruised past 10-men Derby in the Championship.
Last man Scott Malone was sent off in only the third minute for bringing down Yakou Meite in the penalty area, with veteran midfielder Adam calmly converting the spot-kick.
Lucas Joao doubled Reading's lead early in the second half after latching on to substitute John Swift's smart pass.
The hosts rounded off their win with three minutes remaining when Meite also netted from the spot after Lucas was forced over by Craig Forsyth.
Derby have failed to win away from home since their opening weekend victory at Huddersfield and their task was made increasingly difficult after referee Michael Salisbury sent off Malone.
Although, Phillip Cocu's side had a number of chances to level in the first-half as Tom Lawrence saw an effort hit the post and Jason Knight struck the ball narrowly over the bar.
Reading could have doubled their lead in the 26th minute, but Sam Baldock could only find the side-netting from Ovie Ejaria's cross, before Royals keeper Rafael Cabral kept out Derby's Martyn Waghorn on the stroke of half-time.
And after Lucas doubled Reading's advantage, the Rams nearly halved the deficit after 66 minutes when Knight struck the crossbar from 20 yards.
But the hosts were otherwise comfortable and deserved their third goal late on, rising to 16th in the Championship - 10 points off the play-offs, ahead of Derby in 17th courtesy of their superior goal difference.
Reading manager Mark Bowen told BBC Radio Berkshire:
"I wanted a fast start and we did that. We've been working on strikers being lively and that passage of movement led to the penalty and the sending off which I was delighted about.
"It can be a difficult situation when you play against ten men; we were probably in a bit of rush to do things because we had the numerical advantage.
"At half-time I said be patient and the chances would come. What I'm pleased about is everything I told the players to do at half-time we did."
Derby boss Phillip Cocu told BBC Radio Derby:
(On Malone's sending off) "If I look back it's a harsh decision, you can give the penalty but it's never a red card.
"The game plan, everything we worked on all week, it (goes) out of the window.
"But it was a great performance by the team, even with ten men we created the best chances on goal and we still played football with courage."
