PIX: Serena battles to victory against Dutch qualifier

'I'm actually super fit and I'm super ready. I feel like I'm ready for anything.'

Serena Williams shook off some COVID-19 layoff rust to grind out a 7-6(6), 3-6, 7-6(0) win over Dutch qualifier Arantxa Rus on Monday to move into the third round of the Western and Southern Open.

Williams' matches are usually a huge drawcard but with no fans allowed due to COVID-19 safety protocols there was an atmosphere of relief rather than excitement after her hard-fought victory.

"I was fine," said Williams, when asked about playing without fans. "At one point I was pumping my fist and saying, 'Come on'.

"I had a crowd in my head or something. It was actually funny to me. For me, it was like there was a crowd there."

Japan's Naomi Osaka, competing in her first WTA singles match since the season resumed, battled past Karolina Muchova 6-7(5), 6-4, 6-2 to set up a clash with Dayana Yastremska.

She was joined in the third round by former champion Victoria Azarenka, who staved off a late comeback attempt by Caroline Garcia to prevail 6-,2 7-6(8).

By the time Williams arrived on court to face her 72nd ranked opponent, she was the highest seed left in the women's draw after number one Karolina Pliskova and number two Sofia Kenin lost their opening matches on Sunday.

Twice Wimbledon champion Petra Kvitova had also departed following a 2-6, 7-5, 6-2 defeat by Marie Bouzkova and Williams needed to draw on all her experience as Rus put her through a near three-hour workout.

Monday marked the first exhausting day in what could be a three-week tennis marathon for the 38-year-old Williams, who will be bidding to end her long search for a record-equalling 24th Grand Slam title at the US Open.

Down 6-5 in the third set and with Rus serving for the match, a drained Williams looked down for the count but she picked herself up to break the Dutchwoman and force a deciding tiebreak. She then moved in for the kill to win it 7-0.

Despite showing signs of fatigue, Williams said she is ready to go.

"I'm actually super fit and I'm super ready," she added. "I feel like I'm ready for anything."