Alexander Zverev defeated Brazilian teenager João Fonseca 7-5, 6-7 (3-7), 6-3 on Friday at the Monaco Masters to set up a third semi-final in a row this year with Jannik Sinner.

Third seed Zverev clinched victory in 2 hours 40 minutes on his second match point. Zverev blew a 3-1 lead in the second set against 19-year-old Fonseca but then got the deciding break for 4-2 in the final set.

"It's the first week on clay for all of us so it is not always the best tennis. The timing is lacking here and there but there is improvement. I am very happy to be in the semi-finals," Zverev said.

In the last four, Zverev will face world number two Sinner, who ousted Felix Auger-Aliassime 6-3, 6-4 for a 20th straight Masters event victory, a feat previously only achieved by Roger Federer, Rafael Nadal and Novak Djokovic.

Sinner broke once in each set en route to victory in 92 minutes.

He will also like his chances against Zverev who he beat in straight sets in the semis of the recent Indian Wells and Miami Masters events en route to the titles there.

Sinner can reclaim the world number one position from Spain's Carlos Alcaraz in Monaco.

Alcaraz plays Alexander Bublik in his quarter-final and the tournament could culminate in a duel between him and Sinner for the trophy and the top of the rankings on Sunday.