Lorenzo Musetti won the first ATP Tour title of his career as he defeated fellow up-and-comer Carlos Alcaraz in Sunday's Hamburg European Open final.

Top seed Alcaraz ensured he would become the youngest player in the top five of the ATP rankings since Rafael Nadal in 2005 with his semi-final victory over Alex Molcan.

But the 19-year-old paid the price for an error-strewn display on Sunday, as Musetti, 20, took the crown 6-4 6-7 (6-8) 6-4.

Alcaraz was guilty of a slow start on the clay, with four wild unforced errors helping Musetti go a break up after the very first game. Although the Spaniard instantly hit back, his opponent gobbled up his next break point to take a 4-3 lead en route to winning the set.

Musetti then took charge early on in the second to go 2-0 ahead, but Alcaraz showed admirable resolve to see off a couple of match points and level the set at 5-5, before remarkably tying the contest in a tie-break that saw three more championship points squandered.

The deciding set was evenly contested almost throughout, until Musetti broke serve to make it 6-4 and take the match on his sixth championship point as Alcaraz hit a backhand long.

On a momentous day for the Italian, his jubilation was plain to see as he spoke afterwards.

"I have no words because it was a rollercoaster until the end," Musetti said on court. "I had so many match points. Carlos was so good on the match points, [I had] so many chances.

"But I think the key of the match was to keep calm and [have] all the patience [with] myself because it was really not easy.

"Carlos was putting so much effort in the match points when he was down, so it was not easy to find the energy to come back.

"But I cannot describe what I am feeling right now. I think I am still dreaming."

On the subject of the five match points he surrendered, Musetti added: "Of course I was really upset, but I tried to not show my opponent my reaction.

"I tried to forgive [myself for] all the match points and all the points [when] I couldn't do it. I think that was the most [important] thing, even for me, because I didn't expect the win after all this rollercoaster, so I'm super happy to be here and to be the champion."

Musetti and Alcaraz could end up meeting again in the coming week in Umag, where the latter is the defending champion and top seed.