Carlos Alcaraz delivered a brutal knockout blow as his fourth ATP Tour title came on home clay at the Barcelona Open on Sunday.

After lifting trophies in Umag, Rio de Janeiro and Miami over the last nine months, Alcaraz landed a first in Spain, his homeland, by fighting off compatriot Pablo Carreno Busta.

The 18-year-old scored a 6-3 6-2 victory in the final, having earlier in the day edged out Alex De Minaur 6-7 (4-7) 7-6 (7-4) 6-4 in a semi-final lasting three hours and 39 minutes.

Alcaraz has been listening to music from the Rocky boxing movies before his matches, notably the classic Eye Of The Tiger from Rocky III.

"I try to listen to that song before every match. It motivates me," he said on Amazon Prime. "When I listen to the music I remember the movie, and it's amazing this big fight that Rocky has and everything that he is trying to have, that experience in every match, and that's what motivates me."

It was already known that Alcaraz would enter the top 10 in the rankings for the first time on Monday, and he is set to go to ninth on that list, with many expecting him to eventually go all the way to the top.

Alcaraz will be the first teenager to enter the top 10 since Andy Murray in 2007, and the youngest since Rafael Nadal moved into the elite pack in April 2005 after winning in Barcelona.

The semi-final involving Alcaraz and De Minaur, and the last-four battle between Carreno Busta and Diego Schwartzman, had both been carried over into finals day, with each match tied at 2-2 in the opening set when rain stopped play on Saturday.

Carreno Busta scored a breezy 6-3 6-4 win over Argentinian Schwartzman and that looked to give the 30-year-old an advantage, but he found the teenage legs of Alcaraz still had plenty of life left in them for the final.

This was the first all-Spanish final in Barcelona since 2013, when Nadal beat Nicolas Almagro, and Alcaraz was clinical.

Carreno Busta drove a backhand wide on set point as Alcaraz took the opener, and the youngster broke for a 4-3 lead in the second set before picking apart Carreno Busta's serve to love to seal victory.

"It means a lot," Alcaraz said. "I've watched this tournament since I was a kid. I've always wanted to play and win this tournament."