Mason spent last season out of action after undergoing heart surgery to replace an aortic valve in October.
He had been given a clean bill of health and was undertaking pre-season training in the Bellerive nets on Thursday when he suffered a seizure.
He was revived by Tasmanian Cricket Association staff and taken to the Royal Hobart Hospital but died after a subsequent heart attack about 4am yesterday.
The former George Town cricketer was described by team-mates and game officials as an "extremely determined and inspirational human being".
NTCA president and former Launceston Club president Phil McGee watched Mason climb through the cricketing ranks.
"It is very, very sad - it was a big shock, I nearly dropped the phone when I was told he was gone," McGee said yesterday.
"Scott was a wonderful person - he had a strong affiliation with the people, he knew where his roots were and he never forgot where he got his start - here in Launceston."
The sudden death has come as a massive blow to the tight- knit Tigers, who were riding high after a record-breaking season.
Former captain Jamie Cox said: "It is just tragic and ironic that a guy whose heart was metaphorically so big and a man who was so courageous that it was the thing in the end that cost him his life.
"A likeable guy, competitive and inspirational, and one of our true team leaders, and we missed him on the field enormously this season, undoubtedly on the field, but nowhere near as much as we will miss him now."
Mason began playing for Scotch-Collegiate before moving to Launceston City.
He made his first-class debut in 1997-98.
"His whole life was cricket and to play for his State and his determination always meant he played well above his talent," McGee said.
TCA club doctor Peter Sexton said Mason's heart attack was caused by a clogging of his heart's main arteries.
He said the condition was unrelated to the player's earlier surgery.
Mason was diagnosed with a heart murmur about 11 years ago.