Along with tour captain Dr Karl Mullen, McKay was the most-experienced forward to travel with the party in 1950 and he led by example once the Lions landed in Australia and New Zealand.
McKay scored more tries than any other forward on tour, crossing the opposition line on 10 occasions during his 15 starts in Lions colours.
The first of those came on his Lions debut against Buller, while, at one stage on tour, McKay scored seven tries in six games including a brace against both Auckland and New South Wales Country.
His foraging skills in the loose and his ability with ball in hand made him an obvious choice for the Test series against both the All Blacks and the Wallabies as the Lions produced a style of rugby that won them numerous plaudits both at home and on tour.
Having been one of the most impressive performers in the first Test in New Zealand, McKay was forced to leave the second Test after just 25 minutes of play. McKay suffered a broken nose and concussion that would rule him out of the games in the lead up to the third Test, yet the selectors had enough faith in him to put him straight back into the side for that third encounter with the All Blacks.
Although the All Blacks won the Test series 3-0 thanks to narrow victories in the second, third and fourth internationals, the Lions won both rubbers against Australia as they ended the tour on a high.
McKay qualified as a doctor at Queen's University Belfast after the Lions returned home but not before he helped Ireland to another championship title. Having completed his studies, McKay decided to emigrate to New Zealand and to an area in which he had spent a great deal of time while touring with the Lions.
Bill McKay's factfile
Date of birth: July 12, 1921
Club: Queen's University Belfast
International caps: Ireland 23
McKay's Lions lowdown
Lions debut: Versus Buller, May 13, 1950
Lions Tests: 6 (All four Tests in NZ and both in Aus in 1950)
Lions non-Test appearances: 10
Total Lions appearances: 16
Lions points: 50* (10 tries) *under the current scoring system
Final Lions appearance: Versus New South Wales, Newcastle, September 4, 1950