Serena Williams was taken to the brink in an attritional Western & Southern Open victory over Arantxa Rus as she continued her US Open preparations in remarkable fashion.
Williams, knocked out of the Top Seed Open in the quarter-finals by Shelby Rogers this month, ultimately prevailed 7-6 (8-6) 3-6 7-6 (7-0) in a match lasting three hours.
But her journey to that point had far more twists and turns than the 38-year-old will have planned for, Williams having had the chance to serve it out at 5-3 in the decider before world number 72 Rus fought back.
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The Dutchwoman deserved her shot in the final-set breaker, but fluffed her lines as Williams finally got the job done in her first competitive outing in the New York bubble.
Williams will now face Maria Sakkari in the next round, but it could just as easily have been Rus going through.
.@serenawilliams battles her way into the round of 16!
— wta (@WTA) August 24, 2020
Defeats Rus 7-6(7), 3-6, 7-6(0).#CInCyTENNIS pic.twitter.com/oRrKAvDwxJ
She had a point for the opening set in the tie-break but a determined Williams drove home a volley at the net to snuff out that hope, before winning the next two points to move ahead.
Rus fought back impressively in the second set, going toe-to-toe with the all-time great and frequently coming out on top.
She picked her moments to force the issue and executed some stunning forehand winners to take the match to a third set.
Williams then clicked into a higher gear, generating greater power and using all her experience to manipulate rallies to her will as she closed in on victory.
However, the plucky Rus refused to relent and the Dutchwoman showed nerves of steel when Williams was a game away from glory, producing confident holds either side of a break to love to pull level at 5-5.
Incredibly, she then moved 6-5 ahead and served for the match, only to surrender the initiative and fade badly in the decisive tie-break.