By Agence France-Presse
Richard Stanton and John Volanthen, who have day jobs as a fireman and internet engineer respectively, negotiated a long and winding path through flooded caverns to find the 12 young boys and their coach nine days after they went missing.
"The British divers Rick and John were at the spearhead" of the forward search party, said Bill Whitehouse of the British Cave Rescue Council, an informal grouping of rescue teams around Britain.
"They managed to dive the last section and get through into the chamber where the missing party were on a ledge above the water."
Whitehouse, who has spoken briefly to the team that also included a third Briton, Robert Harper, as well as other international and Thai experts, described the difficulties of the search.
"They were diving upstream in the system, so they were having to swim against the current or pull themselves along the walls," he told the BBC.
"I gather the actual diving section was about 1.5km, about half of which was completely flooded," he said, adding that the total dive was about three hours.
'A job to do'
Volanthen, an internet engineer in Bristol in the southwest of the country, and Stanton, a fireman from Coventry in central England, are no strangers to difficult dives.
Stanton, in his mid-50s, told his local newspaper in 2012 that his biggest achievement was helping rescue six British soldiers trapped in caves in Mexico.
He and Volanthen also helped in 2010 in an attempt to find Eric Establie, an experienced French potholer who became trapped underground in the Ardeche region of southern France. Establie's remains were found eight days after he went missing.
"All of the cave rescue missions are quite shocking but the most challenging one was in France," Stanton said in the interview, to mark his receipt of an MBE honour from Queen Elizabeth II.
"Myself and another diver were there for 10 days and it was really stressful the whole time. It was a very dangerous dive and a very dangerous cave."
But he insisted cave diving was still only a "hobby" which he started at the age of 18, after watching a documentary about the sport on television.
In Thailand, the team have avoided the media, with Volanthen telling reporters when he arrived at the site: "We've got a job to do".
Volanthen, reported to be in his 40s, told the Sunday Times in a 2013 interview that caving requires a cool head and that "panic and adrenaline are great in certain situations but not in cave-diving".