Will Beer will play his final game for Sussex on Sunday after announcing he will leave the club after 15 years.
The 33-year-old leg-spinner has played 229 games for his home county but Sussex's last T20 of the year, against Hampshire, will be his farewell.
In 2009 he helped Sussex win their first, and to date only, T20 title.
"I've had a great 15-year career with Sussex and loved every minute of it," Beer told the club website. "I will look back with fond memories."
Beer was at the vanguard of the wave of leg-spinners who have become crucial weapons in white-ball cricket when he made his debut in 2008 aged 19.
A year later he took 2-29 from his four overs as Sussex steamrollered Somerset by 63 runs to win the Twenty20 Cup.
With 106 wickets in 135 matches he is Sussex's leading T20 wicket taker and has only conceded 7.35 runs an over.
He also played 66 List A matches and 28 times in first-class cricket, without making a significant impact on the County Championship.
"My career has taken a bit more of a white-ball path throughout the years," Beer said. "So to be a leading wicket-taker in a specific format in Sussex's history is something I am incredibly proud of."
Beer still hopes to play professionally next season but has been taking exams for a career in financial services.
Sussex performance director Keith Greenfield added: "We all wish Will the very best for his next chapter of his life.
"Sussex would like to congratulate him for his career with us and thank him for all the efforts he has put in for the club over the years."