BRISBANE, Australia - No.2 seed Naomi Osaka overcame all that US Open semifinalist Anastasija Sevastova threw at the reigning Grand Slam champion, ultimately advancing, 3-6, 6-0, 6-4 to reach her first semifinal at the Brisbane International.

"I was just trying to stay calm and tell myself that she's one of the best players in the world," Osaka said. "I just had to stay in there and find my chances, just trying to roll with it.

"She was playing really good, and there was nothing that I could really do about that, except probably like rally more and wait for my chance, and I think that's what I did really well in the second set."

Osaka lost both of her 2018 meetings with Sevastova in straight sets, reversing the trend in dramatic fashion on Thursday with a 91-minute victory.

"This match was really important because I think that I can handle power players pretty well. But for me it was always harder to hit against people like her because I don't really know what's coming next," she admitted.

Sevastova began the match similar to how she had in their last two, breaking serve in the opening game. Osaka saved a break point to slow the Latvian's momentum two games later, but dropped serve to lose the opening set after hitting 15 unforced errors to just eight winners.

"In the first set, I was really nervous and I feel like I was making a lot of unforced errors. That was probably the biggest reason why I lost it, but she's a really amazing player and it's always great to play her."

The US Open champion cleaned things up in a hurry to start the second set, leveling the match without losing a game, and hitting just one unforced error.

Breaking early in the decider, Osaka held on for dear life as Sevastova held a break point for 4-4, later forcing the Japanese youngster to serve for the match.

"I was saying, please hit an ace. Please hit an ace," she later laughed. "I was getting really tense towards the end because I felt like I could see the finish line. And I felt like she was playing more relaxed. So, yeah, I really was just thinking, please hit an ace."

Holding to 15, she finished the match with 34 winners to 23 unforced errors and a perfect break point conversion rate (four for four).

Asked if this is the type of match she would have won just six months ago, she replied: "Probably not. I feel like right now I'm really confident in myself, and I feel like the off season training that I've been doing is really paying off. And I'm not sure if I would have had the same feeling six months ago. Six months ago I hadn't won the US Open. I was having a really bad clay season."

Standing between Osaka and a spot in the final is either Lesia Tsurenko or Anett Kontaveit, who contest the second quarterfinal later today.

In the meantime, the 21-year-old has an off-day to explore the sights, already having seen her share of wildlife earlier in the week.

"I went to the koala sanctuary, and I held a snake. That was pretty cool. Apart from that, I'll go anywhere you tell me if you have any recommendations," she smiled.