“We have faced each other a few times so I know him quite well, but with him [Bublik] you never know what’s happening,” said Sinner.
“He deserves to be in the quarter-finals, he beat very tough players. I tried to stay focused on my side and play as solidly as possible because he can have ups and downs so I tried to stay consistent.”
Victory extended Sinner’s winning run at the majors to 19 matches after triumphs at last year’s US Open and the Australian Open in January.
He will meet either sixth seed Novak Djokovic or German third seed Alexander Zverev in the last four.
They face each other at 19:15 BST on Wednesday, after Carlos Alcaraz and Lorenzo Musetti booked a showdown in the other semi-final.
More to follow.
