Ben Osborn scored a superb injury-time winner as Nottingham Forest hit back to beat fierce rivals Derby and relieve the pressure on manager Stuart Pearce.

The Rams were gifted the lead when Henri Lansbury headed Johnny Russell's first-half corner into his own net.

But Britt Assombalonga's scrambled strike deservedly drew Forest level.

And Osborn secured a first win in nine games, shooting home from 18 yards to deny the Rams the chance to go top of the Championship table.

A victory would have taken the Rams three points clear at the summit, prior to the afternoon kick offs.

And although a Forest side lacking confidence and with just two wins from their previous 20 games were far from outclassed, a home win seemed likely when they trailed at the break to Lansbury's unfortunate own goal.

But a much-improved second-half performance ended a miserable run which has seen them lose their last four games and has led to constant speculation that Pearce would be replaced by chairman Fawaz Al Hasawi.

Forest's four-year wait

Forest's victory was their first at Derby since January 2011 when Robert Earnshaw scored the winner. The defeat was the Rams' third at home this season - and only their second in the Championship.

The energy of Derby's wide men Jamie Ward and Russell suggested a different outcome early on - although Forest could easily have been awarded a penalty when Jake Buxton wrestled Michail Antonio to the floor from a corner.

However the hosts were looking the more cohesive and, with Will Hughes dictating play in the centre of midfield, they took the lead when Lansbury lost the flight of Russell's corner and headed it powerfully into his own net at the near post.

The goal sparked a spell of Derby pressure and a succession of set-pieces.

Craig Bryson had a sidefoot effort blocked by Kelvin Wilson and Reds captain Jack Hobbs almost gifted the hosts a second goal when he made a mess of a dangerous ball into the box.

But Forest were beginning to threaten in attack and the impressive Antonio almost teed up a chance for top-scorer Assombalonga after Lansbury's exquisite pass.

The visitors continued to have the better of things after the interval but struggled to create clear chances until the Rams failed to clear a set-piece and Assombalonga was quickest to react and turn the ball in from close range for his 14th goal of the season.

And with the game now open and increasingly frantic, it was Forest who made the most of their new-found impetus when Osborn crashed the ball beyond goalkeeper Lee Grant in time added on.

Derby County head coach Steve McClaren: "I can't fault the first-half performance. We were focused, played when we had to, dominated and restricted them to set-plays. They were playing opportune football.

"We didn't deserve to lose. I think a draw would have been about right. Everybody would have gone away satisfied with a draw. When they equalised, I would have taken the draw.

"But we showed our inexperience at the end, thinking that with 30 seconds left we should go and try to win it. We lost all shape and got punished.

"The first half we played like us, the second half was not us."

Nottingham Forest manager Stuart Pearce: "For the team to deliver a performance like that, it puts a marker down for the rest of the season.

"It's a nice result but it has to be a result that acts as a catalyst and sees us have a good run between now and the summer hopefully, because we have the nucleus of a decent squad here.

"It's important that we now move forward from here and follow it up with another good result in the next game."

Nottingham Forest's Henri Lansbury heads in to his own goal to give Derby County the lead

Henri Lansbury's unfortunate own goal was the 49th time Derby have scored this season

Johnny Russell celebrates Derby's opening goal against Nottingham Forest

Johnny Russell, who set up Derby's opener, has been a key player in their recent good form, scoring seven goals in 15 games

Britt Assombalonga

Assombalonga scored in the reverse fixture at the City Ground and now has 14 goals this season

Ben Osborn (right) celebrates his late winner against Derby at the iPro Stadium

Ben Osborn (right) celebrates his dramatic late winner - his first senior goal

Nottingham Forest fans celebrate the win over fierce rivals Derby County

Forest manager Stuart Pearce has continued to enjoy the backing of Forest fans despite a winless eight-game run

Lineup, Bookings (4) & Substitutions (4)

Derby County

  • 01 Grant
  • 02 Christie
  • 06 Keogh
  • 05 Buxton
  • 03 Forsyth
  • 04 Bryson
  • 33 Mascarell Booked
  • 19 Hughes (Hendrick - 45' )
  • 11 Russell
  • 09 Martin
  • 10 Ward Booked (Bent - 76' )

Substitutes

  • 08 Hendrick
  • 12 Naylor
  • 20 Bennett
  • 21 Roos
  • 27 Calero
  • 32 Shotton
  • 39 Bent

Nottingham Forest

  • 29 de Vries
  • 17 Kane
  • 25 Hobbs
  • 06 Wilson Booked
  • 02 Lichaj
  • 22 Gardner Booked
  • 10 Lansbury
  • 38 Osborn
  • 32 Tesche (Lascelles - 94' )
  • 09 Assombalonga
  • 18 Antonio (McLaughlin - 81' )

Substitutes

  • 01 Darlow
  • 14 Veldwijk
  • 16 Lascelles
  • 21 Paterson
  • 24 Vaughan
  • 27 Burke
  • 30 McLaughlin
Ref: Andy Madley
Att: 32,705

Sorry, we were unable to load match stats, please try again.