Relf was an all-rounder who batted in the middle order and bowled off-breaks at medium pace with great accuracy.

[1] He played Minor Counties cricket for Norfolk, a coaching engagement with the Earl of Wilton at Houghton Hall gaining him a residential qualification.

In the first Test at Johannesburg in 1905–06, he bowled the ball, allegedly down the leg-side, that enabled South Africa to record the first-ever victory over England.

Writing in the 1940s, Dan Reese said, "He was the best cricket coach we have had in New Zealand, being most thorough in his methods and making his young players work at the game.

[8] By this time, Relf's appearances were limited as he had succeeded his father as cricket coach at Wellington College, and he played later for Berkshire in the Minor Counties.