Korda has won all three of his matches in Group B, winning nine sets and dropping just two.

The world number 39 took down Frenchman Hugo Gaston over five sets in a remarkable comeback victory.

He lost the first two sets 4-3, before taking the subsequent three 4-0, 4-3, 4-0 in a mammoth fixture lasting more than two hours.

After the wobbly opener, Korda then found his feet to dispatch Argentina's Sebastian Baez and Italian Lorenzo Musetti in straight sets.

Nakashima won two matches in Group A, both in four sets, versus Argentina's Juan Manuel Cerúndolo and Holger Rune of Denmark, which bookended a defeat to group winner Carlos Alcaraz.

The Spaniard beat him 4-3, 4-1, 4-3.

Alcaraz is set to face Baez at the Palazzetto Lido Sport in the semi-finals after going undefeated in the tournament.

The world number 32 thwarted a potential comeback from Cerundolo to win 4-0, 4-1, 2-4, 4-3 prior to his defeat of Nakashima and a straightforward 4-3, 4-2, 4-0 win over Rune.

The tournament is an annual men's competition for the world's best under-21 players and has taken place in Milan each year since its inception in 2017.

World number 10 and 2019 champion Jannik Sinner of Italy withdrew from this year's edition along with world number 11 Felix Auger-Aliassime of Canada.

The tournament features best-of-five-sets matches, with each set being first to four games.

The winner of the final will receive $142,000 (£106,190/€124,019), with an undefeated champion taking home $400,000 (£299,127/€349,350).