Rafael Nadal suffered his first clay-court loss to the teenager last week in Madrid. A few days after his 19th birthday, Carlos Alcaraz defeated his idol 6-2, 1-6, 6-3 in the quarterfinals to advance to the semifinals. Speaking of the match, Nadal praised his rival and his determination and aggressiveness.Rafa could not predict the outcome of the semi-final between Alcaraz and Novak Djokovic, but admitted that the youngster is ready to beat any opponent on the Tour. Alcaraz showed no sign of nervousness as he fired nearly 40 winners against a 21-time Major …