Bestwick is one of only two bowlers to have hit ten wickets in a single innings for Derbyshire, which he achieved in June 1921; the other was five-time Test cricketer Tommy Mitchell.

Though Bestwick finished with the second-weakest average of his debut season, he had the best bowling figures of 4–163.

The following year, Derbyshire finished in their highest position since the beginning of Bestwick's career, tenth place.

In January 1907, after a night's drinking, he killed a man named William Brown in a fight, although the inquest at the pub the next day brought in a verdict of 'justifiable homicide.

He was fired and went to South Wales, where he remarried and played for Glamorgan in the Minor Counties Championship in 1914.