Following a road traffic accident in 1962, Halfyard retired from cricket to become an umpire but was able to return to the game in 1968.

[2][3] During the 1962 season he took 98 wickets before he was involved in a head-on collision in a road traffic accident whilst driving to a Kent match against Somerset at Weston-super-Mare.

He was badly injured, including breaking his leg, and played only one club match in 1963 whilst attempting to regain his fitness.

[1] He played some Second XI cricket and appeared two matches in 1964 before injuring his achilles tendon and was released by Kent, although the county arranged a benefit season in 1965 which raised over £3,000.

[5] He made his first-class debut for Nottinghamshire against Middlesex in 1968, a season in which, despite questionable fitness, he played every match.

[2] Halfyard played 77 times for Nottinghamshire from 1968 to 1970, with his final first-class match coming for the county against Kent.

[1] Halfyard returned to the first-class umpires panel whilst still representing Cornwall in 1977, although he only played a few matches for the county.