Sinclair played for Wellington from 1955–56 to 1970–71.[2] His first century came against Northern Districts in 1963–64, when he made 102 not out, out of a team total of 138 for 5, to take Wellington to a five-wicket victory almost single-handedly.[4] His highest first-class score was 148, captaining Wellington against the Australians in 1966–67, out of a total of 365 for 7 on the first day.[5]
Sinclair scored three of his six first-class centuries in Tests, though never played in a winning Test side. He captained New Zealand in three Tests (the Second and Third Tests against England in 1965–66, and the First Test against India in 1967–68) and also in the four-match series against the visiting Australian team in 1966–67 and on the brief tour to Australia in 1967–68. He retired from international cricket in 1968 to concentrate on work.[2]
Sinclair's highest Test score was 138 against South Africa in Auckland in 1963–64, made in 345 minutes out of a team total of only 263.[6] It was the only century by either side in the three-Test series; at the time, it was the highest Test score ever attained by a New Zealander in New Zealand.[7] He took two Test wickets in ten overs, both against Pakistan in Lahore in 1964–65, after scoring 130 in the first innings.[8]
Sinclair's short stature was sometimes exploited by pace bowlers. However, he learned how to handle short-pitched deliveries. He was a neat, tidy batsman notable for his cutting and on-drives.[2]Christopher Martin-Jenkins described him thus: "Fair-haired and one of the smallest cricketers ever to appear [for] New Zealand, Barry Sinclair was a sound and often fluent right-handed batsman with an indomitable spirit and an excellent field at cover."[9]
