Learner Tien is into the semi-finals of the Next Gen ATP Finals for a second straight year, having beaten Nicolai Budkov Kjaer in his third group-stage match on Friday.

Tien was perched perilously in the Blue Group after two matches, sitting third following a loss and a defeat, while Budkov Kjaer was second after two victories.

After 82 minutes, Tien emerged a 3-4 (2-7) 4-1 4-2 4-2 victor to advance to the knockouts.

A four-set win for the American was the only scenario that would seal progression for both players, with Rafael Jodar bowing out despite a straight-sets triumph over Martin Landaluce earlier in the day, which took place in front of their compatriot Rafael Nadal.

The Red Group, meanwhile, was topped by Alexander Blockx after the Belgian beat Dino Prizmic 4-3 (7-4) 2-4 4-2 4-0. 

Nishesh Basavareddy overcame Justin Engel in straight sets to claim second place in the group, meaning he will now face Tien in an all-American semi-final.

Classic Learner Tien  #NextGenATPFinals pic.twitter.com/EJScnLAvnz

— Next Gen ATP Finals (@nextgenfinals) December 19, 2025

Data Debrief: Close success takes Tien through

Tien edged a hard-fought encounter against Budkov Kjaer, hitting 28 winners to his opponent's 25 and committing 24 unforced errors to 27 by the Norwegian.

The American did not give up a single break of serve, saving two break points, and he will now look to replicate his run to the 2024 final, which he lost to Joao Fonseca. 

Budkov Kjaer, meanwhile, is the first Norwegian to ever reach the last four at the Next Gen ATP Finals.