Tennis: Serena crushes Venus in flat family US Open showdown, Nadal survives four-hour thriller with Khachanov

Serena Williams returns the ball during her US Open women's singles third round match against her sister Venus at the USTA Billie Jean King National Tennis Center in New York, on Aug 31, 2018.
Serena Williams returns the ball during her US Open women's singles third round match against her sister Venus at the USTA Billie Jean King National Tennis Center in New York, on Aug 31, 2018.PHOTO: AFP/GETTY IMAGES

NEW YORK (REUTERS) - Serena Williams crushed older sister Venus 6-1, 6-2 in a shockingly subdued third-round clash at the US Open on Friday (Aug 31) to stay on track for a record-equalling 24th Grand Slam title.

The meeting between the famed tennis siblings had been hyped as the biggest night of the US Open but turned into a flat, uninspired spectacle as Serena simply outclassed her sister.

The only moment of suspense in a contest all but devoid of drama came in the second game when Serena rolled over on her ankle, drawing gasps from the capacity crowd.

Serena was able to continue but at the first changeover called a medical timeout and had her ankle heavily strapped.

In the end, though, the only pain being felt was by Venus, who suffered the equal worst defeat in 30 matches against her sister.

"This was my best match since my return. I've worked really hard for it... and hopefully everything will keep paying off," Serena said in an on-court interview. "I roll my ankles a lot so I just wanted to get it taped as tight as I could for the rest of the match and see how I feel tomorrow."

Seven times a Grand Slam winner, Venus held her opening serve but it was all downhill from there as a ruthless Serena swept through the next seven games to take the opening set in a breezy 31 minutes and a 2-0 lead in the second.

Venus stopped the skid holding her serve at 2-1 before Serena resumed the mugging by building a 5-1 lead before finishing off her sister with a thumping forehand winner.

The win was met with polite applause, a hug at the net. Otherwise there was no evident joy in the outcome.

"She didn't win that match tonight because I just rolled over. She played untouchable tennis," said Venus.

"I think it's the best match she's ever played against me. I don't think I did a lot wrong. But she just did everything right.

"I never got to really even touch any balls. When your opponent plays like that, it's not really anything to be upset about."

The capacity crowd that surrounded Arthur Ashe Stadium was kept waiting to enter as world No. 1 Rafael Nadal and Russian Karen Khachanov battled inside in a breath-taking clash that set the bar high for the main event.

The world No. 1 eventually prevailed 5-7, 7-5, 7-6 (9-7), 7-6 (7-3).

Not since 2011 has Nadal lost to a Russian but his string of 16 victories stretching back to 2011 looked ready to end along with his US Open title defence when big-hitting Khachanov came out with guns blazing.

The 27th seed kept up the pressure throughout the 4hr 23min thriller that was the Spaniard's longest-ever match at Flushing Meadows.

"I am very happy to be through in a very tough situation," Nadal said in an on-court interview. "There were some tough moments during the match, but he played aggressive. There are things to work on for the next round, but the good thing is I have a chance to improve."