Bresnihan was called up as a replacement on the 1966 tour to Australia, New Zealand and Canada, making 11 appearances.
The then 22-year-old scored a hat-trick of tries in just his second game in Lions colours - a 24-11 win over New Zealand Universities in which there was one other Lions try scorer.
Bresnihan then scored a brace of tries against West Coast/Buller but didn't feature in the Test series against the All Blacks.
He was selected in the original touring party for the 1968 adventure in South Africa, a tour on which he played a further 14 times.
Bresnihan scored two tries on that tour, against Natal early on and against North-East Districts in his final ever Lions game nearly 42 years ago to the day.
He won two Lions Test caps in '68, featuring in the first and second internationals - a narrow loss in Pretoria and a 6-6 draw in Port Elizabeth.
Domestically, Bresnihan was part of the Munster side that famously beat the touring Australians in the year between his two Lions tours.
Away from rugby, he enjoyed a hugely successful career in medicine and as a professor at St Vincent's University Hospital.
A world expert on rheumatology, Bresnihan was awarded a lifetime achievement award by the Irish Society for Rheumatology in September 2009.
His funeral Mass will take place at the Church of the Sacred Heart in Donnybrook tomorrow at 11am.
Bresnihan is survived by his wife, Valerie, and daughters Niamh, Ciara and Lia and son, Rory.