Clijsters retired after the US Open but organised a match to thank her fans, 13 000 of whom turned up at Antwerp Sports Palace, including Crown Prince Philipe and Princess Mathilde.
In a light-hearted encounter, Clijsters was always going to come out on top but still wowed the crowd with the kind of play that made her famous before injuries got the best of her at 29.
Clijsters beat Williams on the way to her last two US Open titles in 2009 and 2010, and she held a 7-6 edge over the American on the WTA Tour.
She also won at Flushing Meadow in 2005 and captured the 2011 Australian Open. – Sapa-AP