Robert Relf played as a boy for Berkshire before qualifying for Sussex, whom he assisted as a professional allrounder from 1905 to 1924, being one of three brothers to play for the county. He then returned to his native county, with whom he continued till the age of 63. Capable of stern defence, he was a highly-consistent run-getter who hit well all round the wicket, with the drive probably his best stroke. His highest innings for the county was 272 not out, when he carried his bat through an innings of 433 against Worcestershire at Eastbourne in 1909, and he exceeded 200 on two other occasions. Six times he hit more than 1,000 runs in a season - from 1908 to 1913 - his best year being 1912 when in all matches he reached an aggregate of 1804 runs at 32.21. He played for Players against Gentlemen at Folkestone in 1925, scoring 73.