CNN  — 

Back against the wall against her sister Venus in grueling conditions, Serena Williams finally found her game.

The 23-time major tennis champion, playing in only her first event since February, rallied back from a break down in the final set to overcome her sister, 3-6, 6-3, 6-4 in the second round of the inaugural Top Seed Open in Lexington, Kentucky.

“Last couple of games, I just wanted to win because I have been losing a lot of those tight sets,” Serena, who had been down 4-2 in the final set, said in a post-match interview.

“So I said ‘I really need to try to win this’… just for my game and my confidence, so I just tried to focus on those last two games,” added the former top-ranked American, who extended her lead over her older sister to 19-12 in career meetings on a hot and humid day.

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