Ronald Winston Barnes (1 January 1941 – 13 December 2002) was a professional tennis player from Brazil who competed in the 1950s and 1960s.

[1] Barnes reached the semifinals of the U.S. National Championships in 1963, beating third seed Dennis Ralston in the quarter finals.

Afterwards Ralston said "I used to think clay was Barnes' best surface, but now I've got to call him a grass player.

[2] Barnes won many points with forehands from the baseline, but also came into the net and scored with many backhand volleys.

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