'Health first': Rafael Nadal withdrawal leaves fans reeling

Tennis fans have been left gutted after Rafael Nadal confirmed he was pulling out of Spain's ATP Cup tie with Australia.

The World No.2 was on Tuesday evening forced to withdraw from his country's opening tie against the home nation after complaining of a stiff lower back.

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The 20-time Grand Slam champion was due to take the court against Australia's top-ranked player Alex De Minaur on Tuesday night, but opted to rest instead as he prepares for the Australian Open next week.

"Hi all, we have decided with Team Spain and my team, to not play today the first match of the ATP Cup here in Melbourne since I have a stiff low back," he tweeted.

Nadal says he hopes to have recovered from the back issue by Thursday, when Spain are set to meet Greece.

Nadal, who is aiming for a record-breaking 21st Slam title in Melbourne, moving him past the injured Roger Federer, played an exhibition in Adelaide on Friday, beating Dominic Thiem 7-5, 6-4.

However, his unfortunate update late on Tuesday left his legion of fans understandably devastated and hopeful about his speedy recovery.

Spanish number two Roberto Bautista Agut will now face de Minaur, while John Millman takes on Pablo Carreno Busta in the opening rubber.

Nadal's great rival Novak Djokovic helped get Serbia off to a dream start in the ATP Cup, backing up his singles victory with a tie-clinching doubles display against Canada.

World No.1 leads Serbia to opening win

Djokovic kicked things off with a battling win over hot-shot Denis Shapovalov, with the World No.1 prevailing 7-5, 7-5 against the Canadian on Rod Laver Arena.

The 33-year-old showed no signs of being hindered by a nasty blister on his racquet hand that troubled him at an Adelaide exhibition last week.

In fact, the 17-time major winner returned 30 minutes after his singles victory to partner Filip Frajinovic in the decisive doubles rubber.

The pair beat Shapovalov and Milos Raonic 7-5, 7-6 (7/4) as defending champions Serbia took the tie against Canada 2-1 in Group A.

"It was a great opening of the season. Playing Shapo is always a great challenge on hardcourts, he is such a dynamic, explosive player," said Djokovic, who was fired up by playing in front of a smattering of noisy Serbian fans.

"I thought we both played on a pretty high level, so I'm really pleased with the way I started the season."

Serbia beat Nadal's Spain in the final of the inaugural and hugely popular tournament last year in Sydney - launched as a rival to the Davis Cup.

It has been slimmed down from 24 teams to 12 this year due to the coronavirus with all matches at Melbourne Park over five days with US$7.5 million at stake, rather than the multi-city format employed in 2020.

On a cool day, big-serving Raonic got Canada off to a blistering start, crushing Dusan Lajovic 6-3, 6-4 in just 79 minutes to give his team a 1-0 lead, with the former world number three, now ranked 15, dropping just eight points on serve while sending down 11 aces.

It was left to Djokovic to level the tie before clinching the doubles rubber.

While Djokovic tasted victory, US Open champion Thiem, who lost to the Serb in a gripping Australian Open final last year, got his season off to a disappointing start.

He slumped 6-2, 6-4 to Italian world number 10 Matteo Berrettini who never allowed the Austrian to get going with his big-swinging game.

Berrettini was under pressure after Austria took the lead in their Group C clash when 100th-ranked Dennis Novak earned one of the biggest wins of his career, upsetting world number 17 Fabio Fognini 6-3, 6-2.

It sent the tie to a deciding doubles with Thiem returning alongside Novak only to crash again, losing 6-1, 6-4 to Berrettini and Fognini.

with AAP

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