Spain's Davis Cup captain Sergi Bruguera has said there are "no words" that can sufficiently describe the scale of Carlos Alcaraz's achievements, as the teenage sensation prepares for this week's group phase.
Bruguera's side will face Serbia, South Korea and Canada in Group B in Valencia, with the top two to progress to the quarter-finals in November.
Rafael Nadal is skipping the event, but Alcaraz will be the star attraction on home soil after becoming the youngest men's world number one in history with his US Open triumph last weekend.
The 19-year-old came through three successive five-set matches, saving a match point against Jannik Sinner in the quarter-finals, before downing Casper Ruud in four sets in a dramatic final.
"We all knew it was going to happen sooner or later," Bruguera said of Alcaraz's maiden Grand Slam title.
"But the way he won three matches in five sets is an incredible effort mentally as well as physically.
"Being the youngest number one in the world -- there aren't any words."
Spain will play their first tie against Serbia, without 21-time major champion Novak Djokovic, on Wednesday.
"He (Alcaraz) is going to come here on Tuesday and hopefully he can recover in time to play," added Bruguera.
Alcaraz only made his Davis Cup debut in a qualifying tie against Romania in March, having been forced to sit out last year's finals after testing positive for Covid.
"What you experience playing Davis Cup is completely different," said Bruguera.
"You play for your country and that's always special. Tennis is a very individual sport.
"Playing a competition like this allows you to grow personally. The important thing is to have players in good form and I think I have that."
Alcaraz will team up with Roberto Bautista Agut, Albert Ramos-Vinolas, Pedro Martinez and Marcel Granollers for Spain.
- Zverev out with ankle injury -
Former world number two Alexander Zverev had been hoping to make his return to the court for Germany in Hamburg this week.
But Zverev said he was unlikely to play again this year, as he is still experiencing "extreme pain" after a setback in his recovery from tearing ankle ligaments during his French Open semi-final against Nadal in June.
"I am very disappointed to miss out on playing this week," the 25-year-old told daviscupfinals.com.
"I have a bone edema issue which causes me quite a lot of pain. I don't know if it happened yesterday or not but yesterday in practice with Oscar (Otte) it got to the point where I couldn't run or walk anymore.
"I subsequently found out that it was a bone edema, which means I won't be able to participate here and it's not a question of days, it's more a question of weeks and most likely even months."
The Germans open their Group C campaign against France on Wednesday before also facing Belgium and Australia.
"If you lose one of the best players in the world from your team then it's a big blow, absolutely," Germany captain Michael Kohlmann said.
The Russian Tennis Federation are the reigning champions, but have been banned from this year's event due to Russia's invasion of Ukraine.
Italy, Croatia, Argentina and Sweden will play in Group A in Bologna, with Britain, Kazakhstan, the Netherlands and the United States in Group D, being held in Glasgow.
There will be high hopes that Britain can replicate their 2015 title win, with Andy Murray and Dan Evans joining Wimbledon semi-finalist Cameron Norrie in the team.