Andy Murray will face 16-year-old Borna Coric in the first rubber of Great Britain's Davis Cup World Group play-off against Croatia tomorrow.
Coric followed in Murray's footsteps by winning the US Open junior title last Saturday and was a surprise choice to be Croatia's number two singles player by captain Zeljko Krajan.
The teenager has a British coach, Ryan Jones, and spends part of his time training in London.
As expected, Dan Evans was picked for the same role by Great Britain captain Leon Smith following his terrific run to the third round in New York.
The 23-year-old is at a new career-high ranking of 149 and will play Friday's second singles rubber against Croatian number one Ivan Dodig, ranked 35.
Smith picked both Evans and British number three James Ward in his original team.
But, having assessed both on clay in Umag this week, Smith has given Evans the nod and made a change to his four-man team, with Jonny Marray replacing Ward.
Murray, who is playing in his first Davis Cup tie for two years, has put himself forward to play in the doubles rubber with Colin Fleming, which means he is scheduled to play on all three days.
Murray and Fleming, who he has known since their junior days, reached the final of the Montreal Masters last month, and the world number three said in New York: "I think that would be the best chance to win the match."
But should Murray play a long match against Coric then former Wimbledon doubles champion Marray will step in to play with his regular partner against Dodig and Mate Pavic.
Britain are aiming to return to the World Group for the first time since beating Croatia in a play-off at Wimbledon six years ago.