Venus Williams prevailed over younger sister Serena 4-6, 6-3, 10-8 in an exhibition match at the Mubadala World Tennis Championship.Serena, 37, broke 38-year-old Venus' serve twice to win the first set, but faltered in the second, dropping three service games on the way to losing 6-3 here on Thursday, reports Efe.The contest went to a super tie-break.While Venus dropped her opening serve, she outlasted Serena to win 10-8."Serena said I was playing well. I think we can only go up from here and that's our plan," Venus said after defeating the winner of 23 Grand Slam titles."It was really fun and so good to see everyone come out to support myself and Venus. It was really fun out here," Serena said.