Carlos Alcaraz (C) poses for a family picture with the ball girls after winning the final match against Alexander Zverev in Madrid on Sunday. AP
The victory in just over an hour, took the 19-year-old's winning streak to 10 matches and gave him a second consecutive title after victory last month in Barcelona.
Alcaraz beat Rafael Nadal and world No.1 Novak Djokovic on his way to the Madrid final — a first in a clay court tournament — and will climb to No.6 in the world on Monday.
Alcaraz, who turned 19 on Thursday, captured a second ATP Masters 1000 level title after Miami in March. The only younger player to reach that milestone was Nadal, who won in Monte Carlo and Rome when they he was 18.
"This tournament is special for me because it's a tournament I came and watched when I was seven or eight," said Alcaraz. The fans offered him noisy support.
"It was a spectacular atmosphere," he said. "I was able to win with the support of all the people."
Carlos Alcaraz (C) poses for a family picture with ball girls and boys after winning the final match in Madrid. AP
The German second seed was impressed. "Right now you are the best player in the world. Even though you are still five years old you are still beating us all," he told Alcaraz on court after the match.
Alcaraz did not allow Zverev a single break point in the match while putting pressure on the German's serve. Alcaraz broke in the sixth game and comfortably held his serve to take the first set.
The German second seed, had come into the final with a nine-match winning streak in Madrid, but, after holding in the first game of the second set, he unravelled.
Alcaraz galloped through the next five games and into a 0-40 lead, Zverev saved three match points but then double-faulted on deuce and again on the fourth match point.
The German saved three but then served a fifth double fault of the match to hand Alcaraz victory.
"This is tennis," said Zverev. "You cannot be perfect every day."
"Even though I lost quite badly today this is still my favourite court in the world," added Zverev, a champion in the Spanish capital in 2018 and 2021.