The first set in Barcelona was a high-quality encounter between two players born just six days apart and who have been playing one another since their teens.

Alcaraz broke first, thumping his forehand with increasing ferocity, but Rune was equally impressive to immediately force the match back on serve.

Both aggressive baseliners, Alcaraz and Rune sent the ball thudding around Pista Rafael Nadal, but Rune was superior at the net, winning 12 of 16 points there.

Monte Carlo champion Alcaraz fended off four set points but a long forehand in the tie-break handed the initiative to Rune.

Again, Alcaraz had his chances, missing two break points in Rune's first service game. But at 2-1 up, he left the court for a medical timeout, and could not find his rhythm on his return.

Rune reeled off the next five games, committing 24 unforced errors to Alcaraz's 33, and ultimately secured victory on a missed Alcaraz forehand.

The pair are set to play in the Madrid Masters, which begins on Tuesday.

In the men's doubles final, Britain's Luke Johnson and Dutch partner Sander Arends triumphed 6-3 6-7 (1-7) 10-6 against Britis pair Joe Salisbury and Neal Skupski.