21. Lleyton Hewitt, $15 Million
Hewitt made an emotional farewell to tennis in January 2016 when he retired after a 18 year career.
Regarded as the best Australian tennis player ever, the Aussie won 30 career titles including a win at Wimbledon in 2002.
20. Jim Thomas, $15 Million
Maybe a surprise, but doubles professional Jim Thomas is 20th in our list.
Now retired, Thomas works with at-risk children in the State of Ohio.
Now retired, Stanford University graduate Jim Thomas was a force to be reckoned with on the doubles circuit, reaching the semi-finals of the 2005 US Open with teammate Paul Goldstein.
Out of professional tennis since 2008, Thomas, with an approximate net worth of $15 million works with at-risk children in his home State of Ohio.