The Italian, who reached a career-high of No 2 in the rankings on the back of his Miami Open win, slipped to No 3 behind Alcaraz in the Live Rankings as he has 360 points to defend at the ATP Masters event while the Spaniard had no points to defend.
With Alcaraz withdrawing from the tournament due to injury, all Sinner has to do to stay ahead in their is reach the semi-final and he is now within touching distance
The reigning Australian Open champion eased to a straight sets win over Jan-Lennard Struff with minimum fuss despite failing to consolidate an early break in the first set.
Sinner broke Struff in the third game of the set before surrendering the advantage right back to his rival.
However, 22-year-old would not face another break point in the match and broke the German’s serve three more times on his way to a 6-4, 6-2 win.
The slip-up early on aside, Sinner believes he did a great job of negating the threats posed by the German.
“He’s a dangerous player for sure. I had to be very, very careful,” he said.
“I broke him quite early and then he broke me back. I knew it was going to be really tough, but I guess I returned really well, especially on second serves. I can be very happy.”
Sinner won 85 per cent of his first-serve points (22/26) in a clinical march to victory in Monte Carlo.
The Italian is delighted to be through to the last eight where he will face either Holger Rune or Grigor Dimitrov.
“I’m happy. Every match is different. I’m happy again to be in the next round,” Sinner said.
“It’s going to be really tough.
“Against both players I’ve always had very tough battles, tough matches.
“I’m looking forward to it and as always, I’m going to have to raise the level if I want to win. Let’s see.”
Sinner feels that he is physically better prepared to face the challenges of the clay swing this season even if he hasn’t set out to do anything differently.
He still believes that he can make further progress on the surface and be a big title threat on clay.
“I think it’s, I won’t say easier, but for sure the physicality, I have grown, and especially on this surface can help a lot. If you feel more confident, then stronger physically,” Sinner told reporters in Monte Carlo.
