By Fernie Ruano Jr.

Not even a 1-hour rain delay that sent a lively Stadium Court crowd scurrying for cover at the Tennis Center of Crandon Park in Key Biscayne could dampen another solid performance by No. 1 seed Serena Williams, a 6-3, 6-1 winner over upstart American Coco Vandeweghe Monday afternoon in the women’s fourth round at the 2014 Sony Open Tennis.

Into the quarters, Williams is set to meet No.5 Angelique Kerber, who held off a resilient Ekaterina Makarova 6-4, 1-6, 6-3. “She had such an amazing serve,” said Williams, who had just 13 unforced errors despite having to deal with the rainy elements for the second consecutive match. “I just hoped I’d touch the ball.”

In other action from the Day Session, Australian Open winner Stanislas Wawrinka looked impressive in his 7-5, 6-4 victory over Edouard Roger-Vasselin of France; Alexandr Dolgopolov of the Ukraine continues his ascent as he took out Dusan Lajovic of Serbia after dropping the first set 3-6, 6-0, 7-6(5); and Germany’s Benjamin Becker upended Aljaz Bedene of Slovakia 6-3, 7-5.

Williams, a women’s record six-time Key Biscayne champion, needed 79 minutes to finish off powerful Vandeweghe, who sporadically caused Williams problems with up to 122 mile-and-hour serves. At one point, Vanderweghe had the world’s No. 1 doing a spilt on the hard court after holding serve in the fourth game of the first set, thanks to a beautifully placed volley shot to even things up at 2-2.

But despite her effort, No. 104-ranked Vandeweghe, niece of former NBA sharpshooter Kiki Vandeweghe, could do little against the defending champion, who has dropped only 1 of 7 sets in the tournament, and ran her all-time record to 64-7 in Key Biscayne. Williams’ serve, who many experts argue is the best in the history of the women’s game, was in fine form as she won 76% of her first serve points, including 4 aces.

“Well, I’m happy with the matches I was able to put together here,” said Vandeweghe, facing a world No. 1 for the first time in her career. “I mean beating two, you know Top 20 players – well, Anastasia is 21 – (and) going through qualifying and those tough matches I think was a big step. You know, just improving from there.”

Ahead 3-2 in the first set, Williams broke Vandeweghe in the sixth game to take an early two game lead before the rain halted play.