Preston North End's 1-0 Capital One Cup victory against rivals Blackpool was marred by a pitch invasion which resulted in a horse trampling on a steward.
Tom Clarke's 87th minute winner at Deepdale sparked a jubilant invasion at the final whistle, as hundreds of Preston supporters poured onto the pitch to goad visiting Blackpool fans.
Police deployed horses to control the crowds, but one of the stewards was trod on after after he fell to the ground while trying to contain one of the fans.
The steward was treated by police and medics, and taken away on a stretcher to be x-rayed. A Football Association investigation is inevitable.
The west Lancashire derby has been played in all four tiers of the Football League and the clubs' stadiums are only 17 miles apart.
Former Preston manager Gary Peters treated the rivalry so intensely he refused to use the word "Blackpool" in public, referring to the Tangerines instead as "that lot with the tower".
Preston's victory represented a significant coup considering they play in League One, whereas Blackpool play in the Championship.