The Rams suffered their first defeat in six matches as a goal from Michael Bostwick and a second-half brace from Saido Berahino sealed a 3-0 victory for Peterborough United.
Bostwick’s spectacular effort after half-an-hour put the Posh in a goal ahead at the break, before Berahino struck twice – his second in stoppage time at a chilly London Road.
'Keeper Adam Legzdins
saved Lee Tomlin's second-half penalty, but the visitors' hopes of extending a five-game unbeaten run were hit when Jake Buxton was shown his second yellow card.
Darren Ferguson identified the Rams’ swift counter attacks as something the home side needed to be wary of, and in the opening 15 minutes, with Peterborough set-up in a 5-3-2 formation, Derby struggled to penetrate the Posh’s back-line.
However, the Rams did have a half-chance in the opening five minutes to take the lead, as Paul Coutts’ corner from the right was nodded wide by central defender Richard Keogh.
As the first-half went on, Derby began to take control of the midfield battle, and Will Hughes’ strong tackle on Grant McCann freed Theo Robinson, but the former Millwall striker sent a 25-yard effort narrowly wide of Bobby Olejnik’s goal.
The Posh fired a warning sign on 27 minutes as Berahino flashed a shot wide of Adam Legzdins
’ near post from a tight angle, following George Boyd’s through ball.
The West Bromwich Albion loanee’s effort was a sign of things to come, as just three minutes later the home side took the lead.
With half-an-hour gone, Grant McCann’s in-swinging corner was cleared to the edge of the area by Hughes, but former Stevenage utility man Bostwich spectacularly volleyed the ball into the roof of the net, despite Gareth Roberts’ best efforts.
Then the Posh had two chances in quick succession to double their advantage. Firstly, George Boyd’s 20-yard effort looked destined for the bottom corner, but thankfully for the Rams, Legzdins was at full stretch to divert the ball behind. The home side’s second opportunity was even closer, as Berehino’s drive was pushed onto the crossbar by the Rams’ shot-stopper.
Derby were almost back on level terms in the 40th minute, when Coutts’ clever flick played in Conor Sammon, but the former Wigan Athletic striker dragged his effort wide of goal from a tight angle.
The Rams ended the half on top with Michael Jacobs and Sammon both tame efforts comfortably held by home goalkeeper Olejnik.
Robinson bent a 20-yard effort wide shortly after the restart, whilst the 23-year-old striker came within inches of an equaliser moments later.
Sammon released John Brayford down the right; the former Crewe Alexandra defender drove forward in attack and laid the ball across goal towards the onrushing Robinson, who got ahead of his marker but side footed a close-range effort against the post.
On 57 minutes the home side had a golden opportunity to double their advantage. Rams captain Keogh was controversially penalised for a foul on Boyd in the box, and despite the former Coventry City defender’s protest claiming he won the ball, referee Hooper pointed to the spot.
However to the Rams’ delight, Legzdins pulled off a terrific stop to deny Lee Tomlin from the resulting spot-kick, before Jake Buxton nodded the rebound behind to safety.
The Rams’ joy was short lived, as on 70 minutes Boyd burst forward towards goal, but the Scottish international was brought to a halt by the leg of Buxton. To the defender’s dismay, the former Burton Albion man was brandished his second yellow card of the game, despite the away side’s appeals claiming he touched the ball first.
Keogh produced some fine blocks in the final 10 minutes, including terrific last ditch tackle on substitute Danny Swanson.
Despite the Rams’ endeavour, Posh made the game safe in the 84th minute. Berahino’s shot from the edge of the area trickled in at the near post off Legzdins, who could not get enough on the ball to keep it out.
Although the Rams fought until the very end, Berahino fired past Legzdins from a tight angle in stoppage time to seal a 3-0 win.
Derby County: Legzdins (GK); Brayford, Buxton, Keogh, Roberts (Tyson 79); Coutts, Hughes, Hendrick (O’Connor 84), Jacobs (O’Brien 72); Robinson, Sammon.
Subs Not Used: Deeney (GK), Bennett, Davies, Freeman.
Peterborough United: Olejnik (GK); Alcock, Brisley, Knight-Percival; Little, Bostwick, McCann, Nthe, Tomlin (Sinclair 79); Boyd (Swanson 75), Berahino.
Subs Not Used: Richardson (GK), Zakuani, Barnett, Newell, Ferdinand.