A motorcyclist suffered a suspected broken leg on the A583 Blackpool Road near The Lea Gate pub.
Congestion was building up in both directions towards Clifton and Riversway at Preston.
A police spokesman said the accident was first reported at around 4.30pm.
Emergency services were trying to clear the road as quickly as possible.
It is not know whether any other vehicles were involved in the incident.
Delays of more than 20 minutes were reported at around 5.30pm.
The road was clear by around 7.30pm,