Arsonists are believed to have set fire to the club house of a former golf club in Ingol - the future site of Preston North End's new training ground.
Four fire crews from Preston, Fulwood and Penwortham were called to the blaze at the former Ingol Village Golf Club, off Tanterton Hall Road at around 2am on Thursday (April 11).
The fire involved wooden boarding that had been fitted over windows to protect the vacant building from vandals.
It is the second former golf club site to be set ablaze in just 12 hours.
On Wednesday (April 10) at around 2pm, fire crews battled a blaze at the former Fishwick Hall golf club, off Merrick Avenue.
The cause of both fires is believed to be suspicious.
The fire at the former Fishwick Hall golf club is understood to have begun in a maintenance shed and involved a diesel tank.
A spokesman for Lancashire Fire and Rescue said: "Four fire crews from Preston, Fulwood and Penwortham attended a fire at a commercial premises on Tanterton Hall Road, Preston.
"The fire involved the external area of a window and some boarding on a disused, single storey building.
"Firefighters gained access to the property and used a hose reel to extinguish the fire.
"Crews were in attendance approximately one hour and twenty minutes.
"The fire is believed to have been started deliberately and a full investigation alongside colleagues from the police is now underway."
Lancashire Police confirmed that a police investigation has been launched into the cause of the fires.
But the force could not confirm whether the fires are related at this stage.
A police spokesman said: "We were called by the fire service at around 2.25am yesterday (April 11) to the report of a small fire, believed to have been started deliberately, at the side of Ingol Golf Club on Tanterton Hall Road.
"It is believed that someone had set fire to a wooden board. Enquiries are on-going."
Anyone with information should call 101, quoting log number 0095 of April 12.