Diego Schwartzman suffered a similar fate to fellow ATP Finals debutant Andrey Rublev, as the Argentine was brushed aside by five-time champion Novak Djokovic on Monday.

Russian Rublev barely laid a glove on 20-time Grand Slam champion Rafael Nadal during a straight sets loss and Schwartzman looked equally powerless to prevent a sixth loss from six meetings with the clinical Djokovic, subsiding 6-3, 6-2.

The Serb dropped his serve early on at the virtually empty O2 Arena, where on Sunday he was presented with the ATP’s end-of-year No. 1one award for a record-equalling sixth time. But from that moment on he was immaculate.

“I was very happy the way I played in the second set when I started swinging through the ball,” Djokovic said on court.

The 33-year-old world No.1 is bidding to win the title for the first time since 2015 and equal Roger Federer’s six.

Nadal, who had struggled at the ATP’s year-ender with two runner-up finishes in London as his best showings, breezed past Rublev 6-3, 6-4.

Austrian Dominic Thiem got his campaign off to a fine start with a 7-6 (7-5), 4-6, 6-3 victory over Stefanos Tsitsipas. Nadal will face Thiem on Tuesday.

After winning the French Open last month for a 13th time, Nadal sounded unsure whether he would appear in London.

The fact that he is here, with London in Covid-19 lockdown and the O2 Arena without any fans, shows that he regards it as a great opportunity to finally win the title.

“I think it’s a positive start,” Nadal said. “Always here the first match is tricky. You are playing the best of the best. Now I have a super tough match against Dominic.”

With no fans allowed, the atmosphere felt depressingly flat in the cavernous arena.

The world No.3 Thiem said it was hard to play in front of empty seats.

“If you have a huge win like today and you get the atmosphere from 17,000 people, it brings so much positive energy, and all of this is missing,” Thiem said.