Sinner powered his way past world No. 1 Alcaraz to claim victory in the final for a second successive year and he was presented with a golden racket that will be one of the most valuable items in his growing collection of prizes.
Sinner collected a mega $6million after winning just six sets in the exhibition event in Riyadh and he was a comprehensive victor against his great rival Alcaraz.
World No. 2 Sinner was well beaten by Alcaraz in their last meeting at the US Open final, but the Italian took an early grip on the first set when he broke in the opening game and he did not relent until he sealed the comfortable and highly lucrative win.
"When Jannik is playing at this level, it's always difficult. I think everybody could enjoy his tennis today. It was really high level of tennis.
"Sometimes it seems like he's playing ping pong, so it's not funny, to be honest, being at the other side of the net but I always said that.
"When he plays such great tennis, it gives me motivation just to then go to the practice court, give him 100 per cent, try to be better. Sometimes he's annoying, but at the same time he gives me extra motivation.
"We have a special friendship off the court, which is great. Sometimes people think when two tennis players are competing for the great things, are giving their best on the court, they cannot have a great friendship. I think we show it's possible as well."
Sinner also gave his verdict as he said: "It's great to have rivals. We have a great rivalry. But we also have a special friendship.
"First of all, it's always nice to share the court with Carlos. You've done an incredible job throughout the whole season, working very hard, winning incredible titles, titles after title.
"So thanks actually for leaving one also for me at the moment! But no, we come here because we love to play here, we love the atmosphere. Thanks for coming, for sharing.
"Carlos, because especially this season we played many, many times, I lost also many times against Carlos, it's a huge pleasure and and an honour to share the court with him, but at the same time, you want to get better as a tennis player."
All six players who participated in the Six Kings Slam earned a guaranteed $1.5 million, with Novak Djokovic, Taylor Fritz, Stefanos Tsitsipas and Alexander Zverev all collecting the huge appearance fee.
Now Sinner has added an additional $4.5m to his prize fund and he was also handed a golden racket that is reported to be worth around $250,000.
The next possible destination for this compelling rivalry between Alcaraz and Sinner to continue will be at the Paris Masters, but a more likely meeting will come at the end-of-season ATP Finals in front of Sinner's home fans in Turin.