The kingdom is putting on the richest tennis exhibition in history, but its wider ambitions in the sport have contracted.

Rafael Nadal starts his pre-retirement farewell tour against Carlos Alcaraz on Thursday at the Six Kings Slam, and Novak Djokovic faces Jannik Sinner at the exhibition event that awards money but no ATP ranking points and is Saudi Arabia's latest foray into tennis.

Carlos Alcaraz, winner of four majors, crushed the Dane Holger Rune (6-4 and 6-2) in his first game and now will face Nadal in the semi-finals of the tournament with this set to be the last ever game between the two idols of Spanish tennis, with the Davis Cup in Malaga next month set to mark Nadal’s definitive farewell from the sport.

When is Nadal vs Alcaraz? Start time today and how to watch Six Kings Slam tennis live on TV - Spain duo go head to head in Riyadh for the final time before Rafael Nadal retires next month

Sinner recently won the Shanghai Masters title, and on his way to the title at the ATP Masters 1000 event, he beat Medvedev. It was their 14th match, and after the Russian won the first six matches, the Italian managed to level the H2H to 7-7.

The Six Kings Slam is an exhibition event for a half-dozen men that awards money but no ATP ranking points and is Saudi Arabia’s latest foray into tennis.

Sinner studs Medvedev at Six Kings exhibition

The first day of the Six Kings Slam started with a highly anticipated match between World No. 1 Jannik Sinner and No. 5 Daniil Medvedev. Unfortunately for tennis fans, the exhibition was hardly competitive.

The Six Kings Slam is an exhibition tennis tournament held in Riyadh, Saudi Arabia. It will officially kick off on Wednesday and features six prominent tennis players.