The score might not indicate it, but Jannik Sinner said his 6-1, 6-2 quarterfinal victory over Learner Tien at the BNP Paribas Open Thursday was actually quite tough.

"You know, we know each other very well, so try to, you know, being as consistent as possible," Sinner said after advancing to the semifinal at the Indian Wells Tennis Garden. "In the same time, him, for sure, he will change couple of things. So I have to very careful. I watch couple of matches. He's playing great tennis."

Tien's great tennis wasn't particularly evident Thursday as Sinner, the No. 2 player in the world behind Carlos Alcaraz, took just 66 minutes on Stadium 1 to move forward in the event. Sinner did so on a day when the desert heat was impacting numerous players, but the Italian star said he was fine.

"I felt quite comfortable. I came here quite early, and the week before the tournament it was very hot, so that helps me or helped me for sure," Sinner said. "And now, I try to be ready for the next match."

That next match will be against No. 4 Alexander Zverev, who also had a straight-set quarterfinals victory Thursday.

"I'm looking forward to this. These are the matches I practice for," Sinner said. "Semifinals of big tournaments, stages are getting bigger and bigger, so very happy to be here."

Sinner did say the way the match developed was good for him on a hot day.

"I felt like it helped a lot, being up quite early breaks in the first and second set," he said. "So very happy."

Thursday's match was never really in doubt, with Sinner winner 11 of the first 13 game before Tien held serve to trailed 5-2 in the second set, a game that merely forced the match to go past the one-hour mark. Much of the match was based on the players' serves, with Sinner recording 10 aces to four for the No. 25-seeded Tien, and Tien having five double faults to just one for Sinner. Sinner won 83 percent of the points on his first service compared to just 48 percent for Tien.

Despite the results Thursday, Sinner had high praise for the American Tien, who at just 20 is playing at Indian Wells for just the second time.

"I feel like he's improving a lot. Regardless of the result of today, I feel like he's improving," said Sinner, himself just 24. "The groundstrokes are getting stronger. Physically, he's improving a lot, you know.

"So he's going to be a very tough, tough player in the future to beat, of course. He's shown this already against incredible players in the past and also in the present," Sinner added. "So it's going be very interesting to see how he's going to evolve."

This article originally appeared on Palm Springs Desert Sun: Sinner coasts into BNP Paribas semifinals with quick win over Learner Tien