Top seed Karolina Pliskova and fellow Czech Petra Kvitova have advanced to the US Open second round as grand slam tennis returned for the first time in nearly seven full months.

Pliskova defeated Anhelina Kalinina 6-4 6-0 victory as the Open started without spectators amid the coronavirus pandemic.

There were about 15 people, including reporters, scattered in the stands of an arena that holds about 14,000.

Sixth-seeded Kvitova easily beat Irina-Camelia Begu 6-3 6-2 but admitted it took some time getting used to playing in front of the empty seats at Flushing Meadows.

“I had to motivate myself from the beginning to the end,” the twice Wimbledon champion said after converting four of five break-point opportunities and firing 23 winners to defeat her Romanian opponent.

Kvitova also lamented the lack of crowd support at the event, which is being played without any fans in attendance due COVID-19 claiming over 180,000 lives in the United States.

“It’s really mentally tough, to be honest,” she added.

Three-time grand slam champion Angelique Kerber, the 2016 winner in New York, also progressed with a 6-4 6-4 win over Australian Ajla Tomljanovic in a nearly empty Louis Armstrong Stadium.

Marketa Vondrousova was the first winner of the tournament, the 2019 French Open runner-up ousting Greet Minnen 6-1 6-4.

The professional tennis tours were on hiatus from March until August because of the COVID-19 outbreak.

The last grand slam matches were at the Australian Open, which ended in early February.

The French Open was postponed from May to late September and Wimbledon was cancelled for the first time since World War II.