Matej Vydra has now scored 12 goals in 15 appearances in all competitions this season
Matej Vydra scored a hat-trick as Derby beat 10-man Middlesbrough to move into the Championship play-off places.
Vydra smashed a left-footed finish past Darren Randolph following a break to open the scoring early on.
He made it 2-0 from the penalty spot after being caught by Daniel Ayala's trailing leg straight after half-time.
Ayala was sent off for a second yellow card before Vydra seized on a poor Randolph clearance to complete his hat-trick and send the Rams above Boro.
Vydra moved onto 11 Championship goals this season and is now only one strike behind Sheffield United's Leon Clarke in the scoring charts.
His clinical finishing saw Derby leapfrog Boro into sixth place and ensured Garry Monk's side slipped to a sixth league defeat of the season.
The Czech striker, who joined Derby from Watford in August 2016, continued his fine form in front of goal by smashing in Derby's first chance with his left foot.
Boro went close through Britt Assombalonga's header from a corner, but mistakes from Ayala and Randolph were punished by Vydra, meaning Boro drop to seventh.
Middlesbrough manager Garry Monk:
"Talk about shooting yourself in the foot. It was so disappointing to go from playing that well in the first half, where we played some of our best football of the season.
"The one disappointment of the first half was that we weren't ruthless enough. With the chances we created, we should have been winning that game at half-time.
"But the difference was that the one time they were in our half, they were ruthless and clinical with it."
Derby boss Gary Rowett:
"When he (Vydra) gets the ball at his feet and travels, he's a terrific player. He can score with his left foot or his right foot, and he can also head the ball as well. I think he's the best number 10 in the league.
"The most important thing is to get players into a situation where they can play at their best, and I think that's what we've got with him. He's probably a player that needs to feel good about himself.
"He's had a couple of loan moves that didn't really work, so I think he needs to feel that he's valued at the heart of things."
