Australian Open champion Novak Djokovic got his season off to a perfect start with a battling win over Denis Shapovalov in the ATP Cup Tuesday, but Rafael Nadal pulled out injured and world number three Dominic Thiem crashed to defeat.
The Serbian world number one, who will be chasing a ninth Australian Open crown when the year's first Grand Slam begins on Monday, was pushed hard before coming through 7-5, 7-5 against the hot shot Canadian on Rod Laver Arena
Djokovic showed no signs of being hindered by a nasty blister on his racquet hand that troubled him at an Adelaide exhibition last week and returned 30 minutes later alongside Filip Frajinovic to play the decisive doubles rubber.
The pair beat Shapovalov and Milos Raonic 7-5, 7-6 (7/4) as defending champions Serbia took the Group A tie against Canada 2-1.
"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.
"This is a great competition," added Djokovic, who won all eight matches he contested en route to the trophy last year. "We need more competitions where we represent a team, represent our country."
On a cool day, big-serving Raonic got Canada off to a blistering start, crushing Dusan Lajovic 6-3, 6-4 in 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.
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.
Nadal was due to face Australia's Alex de Minaur in an evening Group B clash, but withdrew shortly beforehand with a back niggle.
"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, though, was in his team corner courtside, jumping up and down, and said he hoped to be fit by Thursday, when Spain meet Greece.
In his absence, Spanish number two Roberto Bautista Agut stepped up to face de Minaur and rose to the challenge, bouncing back from losing the opening set to win 4-6, 6-4, 6-4.
Pablo Carreno Busta earlier beat John Millman 6-2, 6-4 to ensure his country claimed the tie.
- Thiem tumbles -
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.
"I'm very happy obviously for myself, but in this competition we're playing for a team, so it's really nice," Berrettini said. "I'm really happy with my performance.
"Playing for your country is something special."
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.
Russia won the day's other tie against Argentina, with Daniil Medvedev and Andrey Rublev both posting wins.