03/23/2015 06:49 am ET Updated May 23, 2015

Bob Hewitt, Ex-Tennis Champion, Guilty Of Rape In South Africa

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JOHANNESBURG, March 23 (Reuters) - Former Grand Slam doubles tennis champion Bob Hewitt was found guilty by a South African court on Monday of two charges of rape and one charge of sexual assault of minors, the radio station Eyewitness News said.

The Australian-born Hewitt, 75, had been charged with assaulting three under-age girls during his time coaching children in South Africa in the 1980s and 1990s.

Hewitt won nine Grand Slam doubles and six Grand Slam mixed doubles titles in the 1960s and 1970s.

He also reached the semi-finals of the men's singles at the Australian Open three times, and won the Davis Cup with South Africa in 1974 after settling there.

The prosecution and defense both presented closing arguments at the South Gauteng High Court in Johannesburg on Monday. Hewitt had pleaded not guilty to all charges.

His doctor said last year that Hewitt remained ill after suffering a stroke in 2010 and a heart attack in 2011. (Reporting by Zandi Shabalala; Editing by James Macharia and Kevin Liffey)