Carlos Alcaraz likely just played his tennis idol Rafael Nadal for the last time in their professional careers during Thursday's semifinal match of the Six Kings Slam. Although the score makes it look like Alcaraz ran away with the match at 6-3, 6-3, the 21-year-old admitted he still had to play his best in order to beat the 22-time major champion.

Rafael Nadal, in his first match since announcing he would be retiring after the Davis Cup next month, lost 6-3, 6-3 to Carlos Alcaraz at the Six Kings Slam on Thursday.

Rafael Nadal will have one final battle with Novak Djokovic when they meet in the Six Kings Slam exhibition event on Saturday. The Spaniard is retiring after next month's Davis Cup finals in Malaga, bringing the curtain down on an incredible career.