In 1958 Grubb won the Gor-Ray Cup, the Assistants' Championship, at Hartsbourne Golf Club. He scored 285 and finished two strokes ahead of Brian Huggett.[1]
Grubb won the Schweppes PGA Close Championship at Western Gailes Golf Club in 1964 taking the first prize of £1,000. He was the only player under par and won by two strokes from Lionel Platts. The event was played in April and was the first important event of the season. Grubb benefited from having played in the United States during the early part of the year and also because, in 1964, the PGA experimented with using the bigger ball, as used in America.[2]
Grubb played in the 6-man England team in the 1967 R.T.V. International Trophy, where he won 5 of his 6 matches and halved the other.[3][4]
Grubb played in the early years of the European Seniors Tour from its start in 1992. He was in the top-10 of the money list in 1992 and 1993. He never won an event on the tour but was a runner-up in the 1992 Forte PGA Seniors Championship behind Tommy Horton and in the 1995 London Masters behind John Bland. In the 1992 Seniors Championship was involved in a playoff with Horton and Christy O'Connor Snr. Grubb hit his second shot out of bounds and Horton took the title with a long birdie putt.[9]
