Blackpool boosted their Coca-Cola Championship play-off hopes but it was a dire day for Derby at Pride Park as the hosts fell to a 2-0 defeat.
Brett Ormerod will try to claim the first goal that went down as a Jake Buxton own goal after the ball deflected off the Derby defender.
There was no doubt the second goal belonged to the Blackpool striker, who might have completed a hat-trick had he not been hauled down by Dean Moxey with five minutes remaining. Moxey received a second yellow card and was subsequently sent off.
Buxton's long-awaited return to the Derby side was one to forget. He started the first six games of the season following his summer switch from neighbours Burton Albion but the centre-half had been out since the end of August with groin and hernia problems.
The early signs on his comeback were not encouraging as he formed part of a Rams defence that persisted with a shoddy offside trap.
Ormerod had already twice broken clean through on goal only to squander both opportunities before his third one-on-one with Stephen Bywater resulted in the ball being deflected past the Derby keeper by Buxton in the 38th minute.
Buxton was then one of the defenders outpaced by Ormerod 11 minutes from time as he raced clear once again to seal the points for Blackpool.
Nigel Clough's side started sluggishly and were fortunate not to fall behind in the second minute when Ormerod hit the crossbar with a 12-yard shot.
Chris Porter, making his first start since the beginning of March after finally recovering from a troublesome hip injury, immediately replied for Derby but his half-volley went over the bar.
Ormerod then went clear once more but again let the Rams off the hook.
Derby's best chances of the first half fell to Robbie Savage but the combative midfielder was unable to take either opportunity.
Ormerod finally made County pay and there was time for Keith Southern to go close before the home team were booed off the field by their own fans at the break.
Both sides had a goal ruled out early in the second half - Paul Dickov for Derby before the Rams' offside trap finally worked to catch out Ormerod.
However, they were not so fortunate in the 79th minute when Ormerod went through and slid the ball under Bywater.
That was the cue for some Derby fans to leave but it was to get worse when Moxey brought down Ormerod.
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