Novak Djokovic celebrated his 38th birthday in style as he reached the semi-finals of the Geneva Open by avenging his Madrid Open loss to Matteo Arnaldi.

The Italian pulled off a shock last month, but Djokovic held firm on Thursday, earning a 6-4 6-4 victory in one hour and 39 minutes.

Djokovic made a strong start in the first set, reeling off three games in a row after Arnaldi had held his serve in the opening game.

He edged in front with little fuss but soon found himself behind as Arnaldi raced into a 4-1 lead in the second set.

In the fifth game, Djokovic overstretched for a forehand before holding the same right knee that underwent surgery last year, but he overcame the scare.

He won the next five games in a row to flip the script on Arnaldi, serving out the clash to love to set up a meeting with either Alexei Popyrin or Cameron Norrie in the last four.

Elsewhere, top seed Taylor Fritz was dismissed by Hubert Hurkacz in straight sets, with the Pole's impressive form continuing in his 6-3 7-6 (7-5) win.

The birthday boy gets his revenge @DjokerNole is semi-final bound after getting past Arnaldi 6-4 6-4.@genevaopen | #GonetGenevaOpen pic.twitter.com/HJ8RkDWJuq

— ATP Tour (@atptour) May 22, 2025

Data Debrief: Birthday treat

Djokovic is still chasing his 100th ATP Tour-level title as he continues his preparation for the French Open, and he had to dig deep.

His serve won him the match last time out against Martin Fucsovics, and though he won 78% of his points on second serve (14/18), it was his return game that won this one.

He won 57% of his second return points (12/21) en route to forcing nine break points and three breaks.