San Francisco Frontiers - Azarenka triumphs in US Open grudge match as Serena and Venus reunite

Azarenka, a former world number one and a two-time major winner, cruised past Marta Kostyuk 6-2, 6-3 in a match dominated in the build-up by bitter exchanges over the conflict in Ukraine.

Last week, Belarusian Azarenka was axed from an exhibition event aimed at raising money for the war-ravaged country.

Ukraine star Kostyuk had refused take part in protest at the presence of Azarenka who she has criticised for a perceived failure to condemn the invasion of her home country.

Belarus is a close ally of Russia and has allowed Moscow to use its territory to launch attacks into Ukraine.

The tension between the two women was evident at the end of their tie on Court 17 with Kostyuk offering just a touch of racquets instead of the customary post-match handshake.

"I wasn't surprised. I don't believe that making a big deal out of it is important. I always shake hands with my opponents," said Azarenka.

"It is what it is. I just move on. I cannot force anybody to shake my hand. It's their decision. How did it make me feel? It's not the most important thing in the world right now."

Kostyuk, the 20-year-old world number 65, said a handshake would not have been appropriate.

"I genuinely wanted to warn her that I'm not going to shake her hand," she said.

"She never came up to me personally to tell me her opinion, what she thinks (about the war)."

Away from the controversy, world number one and French Open champion Iga Swiatek cruised into the third round with a 6-3, 6-2 win over 2017 champion Sloane Stephens.

- Serena's the 'boss' -

Up next for the 21-year-old Pole is a clash with world number 105 Lauren Davis of the United States who has made the last 32 for the first time.

Serena Williams, who is on the verge of retirement after a landmark 27-year career, has been the talk of the tournament with her emotional run to the third round of the singles.

Now the 40-year-old will focus on the women's doubles as she and older sister Venus play a Grand Slam together for the first time since the 2018 French Open.

Their match against Linda Noskova and Lucie Hradecka of the Czech Republic will be the first women's doubles to feature in a night session at the US Open.

Together the sisters have won 14 doubles titles at the Slams with three Olympic gold medals thrown in for good measure.

As a testament to Serena's longevity, she had already won six of her 23 major singles titles before Noskova was even born.

"It was Serena's idea. She's the boss, so do whatever she tells me to do," said 42-year-old Venus when asked why the sisters decided to team up again.

"We have had some great wins. It would be nice to add some more."

They haven't played together in New York, where they have won two titles, since 2014.

Completing the night session on Arthur Ashe Stadium is another career reunion as Rafael Nadal takes on fiery Italian Fabio Fognini for the 18th time.

Nadal, the holder of a record 22 men's Slam titles and a four-time champion in New York, enjoys a 13-4 career lead over Fognini.

However, the Italian famously defeated the Spanish star from two sets down in the third round of the US Open in 2015.

A win on Thursday will allow Australian and French Open champion Nadal to become the first player to secure a spot at this year's ATP Finals.

Carlos Alcaraz, the teenage pretender to the Nadal throne, takes on Argentina's Federico Coria.

R.Moore--SFF