(Photo credit: Mike Frey-Imagn Images)

No. 2 Jannik Sinner saw his record streak of consecutive sets won at ATP Masters 1000 events snapped at 37, but the Italian still managed to beat Czech competitor Tomas Machac 6-1, 6-7 (3), 6-3 to advance to the quarterfinals of the Monte-Carlo Masters on Thursday.

Sinner, whose streak was 13 sets longer than any other since the 1000 series began in 1990, overcame committing more unforced errors (30) than winners (23) by winning 47.2% of his return points and by creating 11 break-point opportunities and converting seven of them.

He lost consecutive service games in the second set to fall behind 5-2 but rallied to force the tiebreaker which he lost handily to see his streak snapped.

'In the second set, I struggled a bit with trying to find the right energy. This can happen. I tried to push myself through, which I've done,' Sinner said. 'Even when you don't feel the best, I'm trying to find ways. That was the case today. I'm happy.'

He'll face No. 6 Canadian Felix-Auger Aliassime for a semifinal spot after the latter's 7-5, 2-2 victory over No. 9 Casper Ruud of Norway, who retired due to an apparent calf injury.

World No. 1 Carlos Alcaraz survived a very sloppy second set to defeat Tomas Martin Etcheverry of Argentina 6-1, 4-6, 6-3 in third-round action.

Of the Spaniard's 47 unforced errors, 23 of them came in the second set. He finished with 45 winners and was never really in danger in the third set, breaking to open up a 3-0 lead and serving out the match from there in two hours and 24 minutes.

'I was playing really well in the first set. I was feeling the ball 10/10,' Alcaraz said. 'Then I started pretty well in the second set as well and had a chance to break his serve in the second game, but I didn't take it. When you don't take the opportunities at this level, you have to run back. He played more aggressive after that, but I would say it was a great fight in the end.'

Alcaraz, who is in danger of losing his World No. 1 spot should Sinner win this event, will face eighth-seeded Alexander Bublik of Kazakhstan for a semifinal spot.

Bublik had an easier time on Thursday, needing just 75 minutes to beat No. 11 Czech Jiri Lehecka 6-2, 7-5. While Lehecka had seven aces and no double faults, he was not able to force a single break point on Bublik, who won 40 of 51 service points (78.4%).

No. 3 Alexander Zverev of Germany is also through to the quarterfinals after a 6-2, 7-5 win over Belgium's Zizou Bergs. No. 5 Alex de Minaur of Australia outlasted Belgian qualifier Alexander Blockx 7-5, 7-6 (4).

In the first of two matches between unseeded competitors, 19-year-old Brazilian Joao Fonseca coasted past Italian wild card Matteo Berrettini 6-3, 6-2 in 73 minutes.

Also, local competitor Valentin Vacherot rallied for a 6-7 (4), 6-3, 6-4 win over Poland's Hubert Hurkacz to advance to the quarterfinals. It's the deepest run a Monegasque player has ever made in Monte Carlo.

--Field Level Media