Germany's Alexander Zverev says he will not take part in a revamped Davis Cup finals showpiece event in Spain in November 2019.
Changes to the 118-year-old team event will see the competition decided in a week-long competition with 18 nations battling for the title.
The first two editions will take place in Madrid's La Caja Magica, the venue for the ATP Tour's Madrid Open.
The ATP have also announced the start of a rival World Team Cup to begin in Australia in January 2020 with the likes of world No.1 Novak Djokovic and 20-time Grand Slam champion Roger Federer likely to prioritise it.
The 21-year-old Zverev, regarded as one of the players to lead men's tennis into a new era, said he would still be available for the Davis Cup qualifying round in February but said he would not play in the November finals week.
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Germany host Hungary in February in Frankfurt and must win to qualify for the finals in the Spanish capital.
"Next year is no ATP World Cup yet, so it's the year after," world No.5 Zverev told reporters after his win over Marin Cilic at the ATP Finals on Monday.
"I'm not going to play Davis Cup in November. I am going to play in February in Germany, in Frankfurt, I'm going to do that.
"The Davis Cup has some serious issues to think about. One of them is the dates.
"I think the date is very important and I think none of the top players will play, except Rafa (Nadal) because it's in Spain.
"I'm very, very sure that a lot of top players will not play. We'll see how it goes."
Zverev sounded more positive about the ATP's World Team Cup.
"I don't know much about it yet. It's still a long time to go for the event," he said.
"Hopefully, it's going to be a good event. Obviously, it's in the first week of the year, so it makes sense to play, and it's in Australia as well.
"So it's not bad schedule-wise."
