MONTE CARLO (REUTERS) - Alexander Zverev survived a first-set blip to break Jannik Sinner's resilience and reach the semi-finals of the Monte Carlo Masters with an epic 5-7 6-3 7-6(5) victory on Friday (April 15).

The German second seed struggled to stay focussed but eventually tamed his 20-year-old opponent in the deciding tiebreak.

Zverev, who battled for more than three hours with the ninth seed, will next meet either defending champion Stefanos Tsitsipas or Argentine Diego Schwartzman.

Earlier, Spain's Alejandro Davidovich Fokina reached his first Masters semi-final by beating American Taylor Fritz 2-6 6-4 6-3 and will take on Bulgarian Grigor Dimitrov.

A terrible service game by Sinner gave Zverev a break for 3-1 but the German failed to hold on to the advantage and the Italian broke back before bagging the opening set.

After an early trade of breaks in the second set, Zverev took a medical timeout and was given a pill by the physiotherapist.

It had the desired effect on the German as he appeared to move more freely to claim the set.

The Italian then appeared to be hampered by a thigh strain and Zverev went on to break for 2-1 in the deciding set.

Although Sinner managed to level the set, he produced a woeful double fault to allow Zverev to move 4-3 ahead.

In yet another twist, Sinner broke back for 5-5 and forced a tiebreak but he just could not get over the finishing line, with Zverev sealing victory on his first match point.