Former footballer Brian Dempsie and Ross French are seeking £200,000 compensation from Strathclyde Fire Board.
Lawyers have agreed the amount of damages to be paid if liability is established.
Fire crews were called to a blaze at a garage near a house in Bothwell, in South Lanarkshire, in February 2008.
As efforts were made to open the front door of the garage brickwork fell on the men.
Ex-Motherwell player Mr Dempsie, 29, of Blackwood, in South Lanarkshire, is a nephew of Scotland star Phil O'Donnell who died of a heart attack while playing for Motherwell.
Mr Dempsie, who was a trainee firefighter at the time, suffered dislocated shoulders, a fractured kneecap, injured ankle and a burn to his lower back.
His colleague, 36, from Uddingston, in South Lanarkshire, suffered severe leg injuries.
Mr French told the Court of Session in Edinburgh when they arrived it was well alight. "The flames were through the roof."
He said he could see the burning garage was far enough away from the house that it was not going to affect it.
The bottom panel of the door was kicked in. "We had trouble getting the door open. It was not budging at the time," he said.
He was told by the watch commander to get equipment for breaking in and returned with a Halligan tool. "It was to break in or get the door off its hinges to enable us to have full access to the building," he said.
He was using the tool with his colleague Mr Dempsie directing a hose through the breached part of the door at flames. "The gable end from the lintel to the ridge collapsed on top of myself and Brian Dempsie," he said.
The fire board's counsel Ian Mackay, QC, suggested the door was opened when the bricks fell, but Mr French said: "I honestly couldn't tell. I was under the bricks at that point."
In the action it is claimed there was no need to force open the front door to fight the fire.
When the crew arrived flames were coming through the roof, most of which had collapsed.
It is said the officer in charge, watch commander James Clark, took the decision the garage's cantilevered front door should be opened to fight the blaze.
In the action they maintain there was no threat to life or property in the immediate vicinity of the garage.
It is claimed Mr Clark was required to undertake "a dynamic risk assessment" and had he done so he would have concluded that opening the door was an unnecessary risk.
The board, which is contesting the action, claims the advantage of opening the door was that it provided a safe way to fight the fire without firefighters having to go into the garage.
The board claims the collapse of the brickwork was caused or contributed to by a type of lintel that had been used.
The hearing continues.