John Gilbert Alexander (born 4 July 1951) is a former Australian politician and former professional tennis player. As a tennis player, Alexander reached a career-high singles rank of No. 8 in the world in 1975. He reached the semi-finals of the Australian Open singles on three occasions, and won the doubles in 1975 and 1982. He also played in the Australian team that won the 1977 Davis Cup. After the end of his playing career, Alexander worked as a tennis commentator and managed various sports-related businesses. Alexander won the Division of Bennelong for the Liberal Party at the 2010 election, and retained the seat in 2013 and 2016. He resigned on 11 November 2017 due to constitutional ineligibility arising from his dual citizenship of the United Kingdom. He renounced his UK citizenship and stood as the Liberal Party candidate at the by-election, held on 16 December 2017, which he won. In November 2021, Alexander announced his retirement from politics. Early life Alexander was born in Sydney. His father, Gilbert Alexander, was born in Essex, England, in 1907 and moved to Australia at the age of three. Tennis career During a tennis career spanning the late 1960s to mid-1980s, Alexander won seven tour singles titles and 27 doubles titles, and earned a total of $1,214,079 (USD) in prize money. He achieved a career best singles ranking of World No. 8 in December 1975. Alexander is the youngest player to represent Australia in the Davis Cup. He was also one of Australia's longest serving Davis Cup players, representing his country from 1968 to 1983. From 1974 to 1986, Alexander served as the resident tennis professional at Lamar Hunt's World Championship Tennis Peachtree World of Tennis Club in Peachtree Corners, Georgia US. Alexander served as captain of the Australian Fed Cup team and worked as a sports commentator for Australian (Channel 7) and British (BBC) television networks for over 20 years. Business career As managing director of Next Generation Clubs Australia, Alexander designed and built sport and fitness clubs; including the Ryde Aquatic Centre in Sydney to host the 2000 Summer Olympic Games water polo event, the development of Memorial Drive in Adelaide into a multi-function health and fitness facility, and Royal King's Park in Perth. In 1995 Alexander served as referee during the first series run of the Australian adaptation of the television series Gladiators. Shortly before his election to Parliament in