World number one Novak Djokovic has backed the new ATP Cup team event, saying it will provide incentives for leading players to take part.

Djokovic appeared with the ATP and Tennis Australia on Thursday to confirm the event will start in January 2020 as a curtain-raiser to the men’s season.

A revamped Davis Cup tournament will take place in November from 2019.

On Wednesday, Djokovic said he thought two rival events within six weeks would not be “good for the sport”.

The 31-year-old Serb said he feared the situation – which he described as “delicate” – could lead to two “average” events.

“I think in the next two years we’ll have both events happening in a very similar format if not the same, six weeks apart,” the 14-time Grand Slam winner said.

“We have the longest season in all sports. We’re just adding events. We kind of have to try to focus on quality rather than quantity.”

“I think creating one event is an ideal scenario and I think outcome for everyone.”

The ATP Cup will have prize money of £11.35m. It will feature 24 nations in six groups of four and up to 750 ranking points will be available for the winners.

Three Australian cities will host the 2020 event, which will run from 3-12 January and lead into the Australian Open, which starts on 20 January.

Meanwhile, the ITF competition will be an 18-team end-of-season event, which will crown the Davis Cup champions.

The controversial proposals to revamp the Davis Cup were backed by national tennis federations in August, although players were not consulted.

Djokovic, who is the ATP Player Council president, said at the launch of the ATP Cup in London that it was an attractive proposal for the players.

“Having ranking points as an option is obviously an incentive for players,” he said.

“We have a lot of incentives and the biggest one, I’m sure, is playing for your country.

“We have the Davis Cup, which has been the most historical team event, and now we have the ATP Cup, which is definitely going to be right up there in terms of the value from the players’ perspective.”

Earlier in the week, Germany’s world number five Alexander Zverev said he felt none of the top players would play in the Davis Cup.

Analysis

Russell Fuller, BBC tennis correspondent

The ATP Cup will almost certainly be an innovative and enjoyable experience, but the fact remains it will go ahead six weeks after the Davis Cup Finals – even though the head of the ATP said that would be “insane”.

What’s more, both events will be very similar in format.

The ATP prize fund is impressive, albeit US$5m less than the money Kosmos is offering for the revamped Davis Cup.

But the ATP can offer the added pull of up to 750 ranking points for members of the winning team at a time of year which suits the players.

November, in contrast, is a terrible time for a team competition as bodies are tired and injuries rife. Kosmos’ founder Gerard Pique wants the Davis Cup to be staged earlier in the year, but ideally needs the co-operation of the ATP.

Talks continue, but unless common ground is found, there remains a major question mark over the long-term sustainability of the Davis Cup.

Marin Cilic fought back to keep alive his hopes of reaching the semi-finals of the ATP Finals for the first time with victory over John Isner.

The Croat, who has won just two of 11 matches in four appearances at the event, triumphed 6-7 (2-7) 6-3 6-4.

The result puts Novak Djokovic into the semi-finals, leaving Cilic, Isner and Alexander Zverev to fight it out for the group’s other spot on Friday.

It was the first singles match of this year’s event to go to a deciding set.

• Are the ATP Finals permutations making your head hurt?
• Live scores, schedule and results
• Alerts: Get tennis news sent to your phone

Cilic holds his nerve

Cilic has something of a reputation as a bottler – the most recent example coming last week in the quarter-finals of the Paris Masters where he lost to Djokovic despite having won the first set.

And there was a moment here when it looked like he might not hold his nerve.

Having secured rare back-to-back breaks against the tour’s leading server to win the second set and take an early advantage in the third, he then inexplicably dropped serve to give Isner hope.

But he then showed his determination – via some first-class returning and a wonderful drop volley – to secure a third successive break.

With Isner holding on to force him to serve for the match, Cilic showed no sign of wobbling as he brought up three match points and took victory when the American returned a looping second serve wide.

“It was very difficult. The first set was extremely tough. John played a great tie-break and I had to stay focused,” said Cilic, whose only other Finals victory came against Kei Nishikori in 2016.

“I served really well and I am really pleased with the win. I felt that I had that momentum towards the end of the second set. I felt the ball well and got some good points on Isner’s serves.

“He hit a few double-faults on the break points – that helped – but I stayed patient and I managed to break back and play some good tennis towards the end.”

Isner faces Zverev on Friday, while Cilic takes on the already-qualified world number one Djokovic with one other semi-final place at stake.

The other group is back in action on Thursday for their final round-robin matches, with Roger Federer against Kevin Anderson after Dominic Thiem takes on Kei Nishikori. All four in that group have a chance of progressing.

Isner let down by double faults

Isner was playing the day after learning of the death of one of his close friends, Kyle Morgan, and he wore the initials KM on his shoes.

As the leading server on the Tour, it was no surprise that he began the match with a thumping 138mph ace.

He delivered a total of 17 aces against Cilic but was let down by six double faults, including the one that handed the Croat the crucial break in the second set.

The American is making his debut at the tournament after enjoying his best year to date – having reached his maiden Grand Slam semi-final at Wimbledon, won his first Masters 1000 title at Miami and finished the season ranked inside the world’s top 10 for the first time.

World number one Novak Djokovic became the first man to reach the semi-finals of the ATP Finals after a clinical win over Alexander Zverev and a favourable result in the group’s other match.

After a very physical and close first set, the 31-year-old Serb ran away with the second to beat the German 6-4 6-1.

Djokovic, chasing a first ATP Finals title since 2015, reached the last four when Marin Cilic beat John Isner later.

“I don’t think it was breathtaking tennis but a win is a win,” he said.

“I played well midway through the second set and started to swing through the ball.

“I had not served that well but he made a lot of unforced errors which helped me to win.”

Indeed, it was a double-fault from Zverev that handed Djokovic the first set and a total of 33 unforced errors that contributed to the 21-year-old’s downfall.

Djokovic plays Cilic in his final round-robin match on Friday, while Zverev takes on Isner.

• Are the ATP Finals permutations making your head hurt?
• Live scores, schedule and results
• Alerts: Get tennis news sent to your phone

Are you Mr Bendy, Novak?

It took until the ninth game of the first set for either player to fashion a break point, Zverev missing two in that game.

Having survived that pressure, Djokovic left it until the perfect time to break in the following game – taking the set when the German double-faulted.

It was an unfortunate way for Zverev to fall behind, having been impressive with his serves until that point, delivering seven aces and in one game firing down three successive serves at more than 140mph.

Tipped by many as a future Grand Slam-winner, Zverev showed some of his talent with some beautiful passing shots but he was up against a player who can contort his body to reach almost anything.

Djokovic met one of Zverev’s body serves with an unconventional placement of his racquet that looked more about shielding his face – but of course the return went in – and later Zverev needed two attempts at a smash to put the ball away, when against any other player the first one would have done.

“That’s a first – ‘Mr Bendy’,” the Serb laughed in his on-court interview. “I am relying on my flexibility a lot. I was fortunate to be surrounded with people who emphasised the importance of stretching and it has paid off.”

Djokovic is favourite to win a sixth title at the end-of-season tournament after a remarkable year in which he came back from elbow surgery to win Wimbledon and the US Open and return to the top of the rankings for the first time in two years.

The top two from the two four-player groups qualify for Saturday’s semi-finals, with the winners of those matches meeting in Sunday’s final.

Where did it go wrong for Zverev?

The turning point of the match was at 4-4 on Djokovic’s serve, when Zverev went 0-30 up. But a forehand and then backhand error wiped out the advantage and the German bounced his racquet off the ground in frustration.

Djokovic netted a forehand to give Zverev a break point, which he wasted by returning long, and the Serb then gave him a second chance with a double-fault but the youngster missed that break point when an attempted lob drifted long.

In the end, Djokovic held his serve with a lovely drop-shot and never looked back.

Three errors in a row in the next game gave Djokovic his first break points of the match and while Zverev saved one of them with a smash, he gave the set away with his only double fault of the first set.

The opening two games of the second set were close, Djokovic whacking his shoes with his racquet when he failed to break in Zverev’s first service game having taken him to deuce.

But after that Djokovic turned the screw, with the German taking only three points in the final five games as the 14-time Grand Slam champion wrapped up victory in one hour and 16 minutes.

“It is important to understand the situation – Zverev is playing against the best player in the world right now, while he is playing some of his best tennis. It’s great for him to understand where he is right now,” former British number one Tim Henman said on BBC TV.

“If he really wants to kick on in the Grand Slams – something which hasn’t really happened so far – then he has to test himself against the level and that was it in a nutshell. It’s very easy to be impatient because he has won so much [three Masters 1000 titles are among his nine ATP titles] but he is still only 21 and is on a journey. Bigger and better things are to come.”

Analysis

Former player and BBC commentator Andrew Castle:

This was from a guy [Djokovic] who was nowhere. He was a lost soul in the last two years after winning the French Open in 2016. He had won everything. But he is re-ignited now. I think it is fantastic to see him back at his best. It is brilliant for the game. Everyone will be watching this and thinking ‘that is a high standard’.

This tournament is finally starting to light up. We have had a lot of ordinary matches but that wasn’t one of them. Djokovic didn’t seem to think it was but if that’s the case then I’d like to see him playing ‘well’.