Serena Williams (right) holds the championship trophy as Li Na (left) holds the runner-up trophy after the final of the Sony Open at Crandon Tennis Center. Williams won 7-5, 6-1. [Photo/Agencies]

KEY BISCAYNE, Florida - Serena Williams won a record seventh Key Biscayne title Saturday when she overcame a slow start and a set point to beat Li Na 7-5, 6-1 at the Sony Open.

Williams surpassed the tournament record of six titles she shared with Andre Agassi. But on a muggy spring afternoon, the No. 1-ranked Williams looked sluggish at the outset and served poorly, and she was broken twice to fall behind 5-2.

"At that moment I felt like I had nothing to lose," Williams said. "I just was able to relax. Whenever I relax, I enjoy myself."

Li held a set point serving at 5-4, but Williams erased it with a backhand winner.

Williams needed another 21 minutes to pull out the set. The final game of the set went to deuce six times, but she finally won it with a booming backhand that Li couldn't handle.

Williams ran to her chair with a satisfied scream, her left fist leading the way. She dominated from there, sweeping the final five games, and closed out the victory with a service winner.

After a succession of happy hops, she was twirling, waving, laughing and mugging for the camera _ a familiar ritual from a familiar champion.

"I think we're going to have to rename this tournament," former top-five player Mary Joe Fernandez said during the trophy ceremony.

It's a commentary on the yawning gap between Williams and the rest of the women's tour that she won in straight sets against the No. 2-ranked player while playing less than her best. She made only 44 percent of her first serves and converted just five of 17 break-point chances.

Even so, Williams extended her winning streak against top-10 opponents to 15 matches.

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