Great Britain will have a team at the inaugural ATP Cup in January after Andy Murray decided to enter the event.
Murray was wavering about whether to use his protected ranking of two to secure Britain's place at the round-robin tournament in Australia, which will kick off the 2020 season.
The event, which is being held in Brisbane, Perth and Sydney, will pit 24 national teams against each other, with the draw taking place on Monday.
The first 18 countries were decided on Friday, and Britain's inclusion depended on Murray, who was wavering until the last minute.
Speaking on Thursday, the Scot said: "If I use my protected (ranking), I will play as the number one player. I think if you are playing in a competition like that, the best player should be picked to play.
"The Australian Open would be the priority for me. And I don't want to go there and not play any matches. So, I am finding that quite a difficult choice to make."
Had Britain needed to rely on current British number one Kyle Edmund, ranked 32, they would not have qualified in the initial 18 and would have been outsiders for the final six teams, who will complete the field in November.
Murray's protected ranking comes from the position he held before the two hip operations that forced him off the singles court for the majority of the last two years.
His current ranking is actually 415, making him the British number 13. He returned to the singles court last month and will play in four straight tournaments in China and Belgium beginning in Zhuhai on September 23 as he builds up his fitness and match sharpness.
The ATP Cup is a rival tournament to Davis Cup and its inclusion in the calendar has been controversial given it will take place less than two months after the first of the new World Cup-style Davis Cup finals in November.
Murray is keen to be part of the GB Davis Cup team, and he added: "I'm very pro team competitions in tennis, I just don't like the week that it (the ATP Cup) is in. ever have done. I don't like that there's two team competitions six weeks apart either. It just doesn't make sense."
Chris Kermode, ATP executive chairman and president, said: "We're delighted to see such a star-studded player field lining up for the inaugural ATP Cup. Our belief was that week one in the calendar, together with Tennis Australia, would work best for player scheduling, and today's announcement is a confirmation of that. Having the top players competing in this new global event is critical, and the ATP Cup looks set to kick off the ATP Tour season in a big way in 2020."
