Miami (AFP) - Three-time winner Venus Williams saved three match points in a three-set victory over Kiki Bertens on Sunday, lining up a fourth-round clash with reigning champion Johanna Konta at the Miami Open.
Williams, ranked eighth in the world, labored nearly three hours to beat 29th-ranked Bertens 5-7, 6-3, 7-5.
The 37-year-old American was cruising with a 5-0 lead in the opening set, but she squandered three set points as Bertens reeled off seven straight games to snatch it.
The second set was another streaky affair, but Williams gained a decisive break for a 5-3 lead and fought off a break point in the next game to force the decider.
The seven-time Grand Slam champion would have to dig deep when she fell 1-4 down to her Dutch opponent in the third.
Bertens served for the match at 5-3 but was unable to convert two match points as Williams broke to put the match back on serve.
Williams would face one more match point against her own serve in the next game, but she held on as Bertens appeared to struggle with cramps in the final games.
Williams sealed the win with an emphatic forehand winner, giving a little leap of elation.
"It didn't look good sometimes, that's why you keep playing until the last point," said Williams, who lifted the trophy in Miami in 1998, 1999 and 2001. "And that's why I love this game."
Konta, whose victory here last year propelled her into the top 10 in the world rankings, advanced with relative ease, beating Belgian Elise Mertens 6-2, 6-1.
Konta exchanged early breaks with Mertens, but gained the upper hand with a break for 3-2 when the Belgian double faulted four times in one game.
It launched a streak of four straight games for Konta that gave the Briton the opening set.
She powered through the second to reach the fourth round, where the 26-year-old will try to get past the last 16 of a tournament for the first time this season.
Puerto Rico's Monica Puig, the 2016 Olympic gold medalist, also reached the fourth round, following up her upset of second-seeded Caroline Wozniacki with a 6-3, 7-5 victory over Greece's Maria Sakkari.