Peterborough recorded successive npower Championship wins at London Road for the first time since March with a comprehensive 3-0 victory over 10-man Derby.
Michael Bostwick gave Posh the half-time lead before a late double from on-loan striker Saido Berahino moved Darren Ferguson's side out of the bottom three ahead of the evening kick-off between Bristol City and Hull.
The margin of victory would have been greater for Posh had it not been for Adam Legzdins who made a handful of good saves, including Lee Tomlin's second-half penalty. However, the Derby goalkeeper was at fault for Berahino's first goal.
The Rams struggled to create chances and their task was made more difficult at 1-0 down when they had Jake Buxton sent off.
After seeing his side record a first home league win of the season in midweek, Ferguson named an unchanged starting line-up. In fact, it was the same matchday squad that was on duty against Huddersfield on Tuesday night.
Gareth Roberts and Jeff Hendrick were restored to the Derby team after recovering from injury as Rams boss Nigel Clough made two changes.
Left-back Roberts, absent for the last three matches with a hamstring problem, replaced James O'Connor who dropped to the substitutes' bench.
Hendrick returned to central midfield after an ankle injury kept him out of the midweek win over Ipswich. The academy product came in for Craig Bryson, who missed out completely after picking up a knock at Portman Road.
Derby defender Richard Keogh headed wide from Paul Coutts' corner early on and Berahino went close for Peterborough with a right-foot shot midway through the first half after cutting in from the right flank.
Posh went ahead after half an hour when Bostwick fired into the top right-hand corner of the goal and had a couple of chances to immediately double their lead.
George Boyd, brilliant against Huddersfield, forced a good save from Legzdins with a 20-yard effort.
Legzdins then tipped over a shot from Berahino when the West Brom teenager threatened from the left side this time.
Conor Sammon failed to get Derby back on level terms after 40 minutes, firing wide from just six yards out.
Robinson came even closer to an equaliser five minutes after half-time when his shot from 12 yards out struck a post.
Tomlin should have put Peterborough 2-0 in front in the 57th minute after Keogh brought down Boyd inside the area but Legzdins saved the resulting penalty.
Derby's task got more difficult when Buxton was booked for the second time in just four minutes. The centre-half's fouls on Berahino and then Boyd resulted in him being sent off after 70 minutes.
And from the following free-kick, Legzdins produced more heroics to keep out Bostwick's shot.
Legzdins then thwarted substitute Danny Swanson with another parrying save but he undid some of his good work with four minutes remaining when he dropped Berahino's shot from the edge of the area over his own goalline.
Berahino added some gloss to the scoreline deep into injury time when he breached the Derby defence and raced clear to beat Legzdins once more.