Robert Maskew Cowper (born 5 October 1940 in Kew, Melbourne, educated at Scotch College Melbourne) was an Australian Test match cricketer in the 1960s, who played Sheffield Shield cricket for Victoria and Western Australia.
He was the son of Dave Cowper, the captain of the Australia national rugby union team. Cowper was a tall, correct left-handed batsmen who was dropped in the 1965-66 Ashes series for slow scoring. When he was recalled for the Fifth Test at Melbourne he made the first Test triple century in Australia; 307 from 589 balls in 727 minutes. Matthew Hayden's 380 against Zimbabwe in 2002–03 is now the highest Test century in Australia, but Cowper's remains the longest.
After his triple century he was never omitted from the Test side until a hand injury forced him out of the Fifth Test in 1968. In the last 13 matches of his Test career (the 1966-67, 1967–68, and 1968 series) he scored 931 runs at 38.79 and took 31 wickets at 25.22. In those 13 matches no other Australian player exceeded 800 runs, and only Graham McKenzie, with 49, took more wickets. Cowper was only 27 when he played his last Test, at Headingley in 1968, almost exactly four years after his first, at Headingley in 1964.
He captained Victoria to victory in the Sheffield Shield in 1969-70, then left cricket altogether to concentrate on his business career.
Remarkably, he averaged an impressive 75.78 in home Tests but only 33.33 overseas. The difference of 42.45 is a Test match record.
Since retiring from playing, he has had a successful career in big business, and has also served as a cricket referee.