Diego De Girolamo scored his first goal for Sheffield United as last season's FA Cup semi-finalists earned a fourth-round replay with a 1-1 draw at Deepdale.
Preston began the brighter and Paul Gallagher opened the scoring on 19 minutes but Italy under-20 international De Girolamo struck midway through the second half for the Blades.
Preston North End have confirmed that the club was contacted today by the National Crime Agency in relation to an investigation into spot-fixing allegations.
A pitch invasion which led to a football steward being trampled by a police horse has been labelled "completely unacceptable" by police chiefs, who vowed to prosecute the troublemakers.
The behaviour towards officers and match stewards from some fans at last night's cup tie derby between Preston North End and Blackpool was criticised as "disgraceful".
Police said "a significant minority of determined people" from both sides were intent on causing trouble on the night and added that those identified would be tracked down and prosecuted.
Two people were arrested for criminal damage to one of the supporters' coaches outside the ground, with another four people held for minor offences.
Superintendent Richard Morgan, of Lancashire Police, said police officers "responded quickly" to the pitch invasion at the end of the Preston-Blackpool match on Monday night. A steward was struck by a police horse during the disorder.
John McDougall, who was reporting from the match for the Press Association, said: "It was a feisty game - not a dirty one - and there was clearly local pride at stake.
"At the end of the game there was a pitch invasion and some of the Preston fans went over towards the Blackpool supporters in the away end.
"Police, both on foot and mounted, formed a wall between the two sets of fans. It took about five or 10 minutes for them to clear the supporters.
"Both managers have condemned the pitch invasion."
Lancashire Police have confirmed they are looking into the incident.
A football steward appeared to be trampled by a police horse following a pitch invasion at the end of the Capital One Cup game between Preston North End and Blackpool tonight.
The steward, who was wearing a hi-vis jacket, was on the Deepdale pitch helping clear fans after the hosts' late winner prompted scores of supporters to run from the stands to congratulate the players.
But one steward appeared to be struck by a police horse as it cantered across the pitch, while another horse - also helping with crowd dispersal - seemed to clip the steward as he lay on the ground.
Tom Clarke headed the only goal as the League One side defeated Lancashire rivals Blackpool.