Just when it looked like she was rolling in to some rhythm heading into next week's Australian Open, Stosur's run was halted by the world No.94 in the quarter-finals.

The Australian went down a break in both sets and was unable to recover to force the match into a third, going down 6-4, 6-4 to the 22-year-old Puerto Rican, ending Australia's presence in the women's draw.

"I think she played exceptionally well," Stosur said.

"She played a hundred times better than every other time I've played against her. All the things – well, not all the things, but a few of the key things – that worked in our previous matches she handled much, much better tonight.

"I have to give credit where credit is due. I don't think I was obviously at my best. You know, she really put me under pressure from the first to the last point and held her nerve and everything else. You know, she played well."

Despite the disappointment, Stosur heads to Melbourne with a lot more confidence than she has had after moral-crushing losses to start the season in years gone by.

"Overall, I'm feeling good. Obviously still room for improvement, which is, I guess, normal for anyone," she said.

"I've got a few days now to get down to Melbourne and practice and keep trying to prepare as best I can and try and play better. So I think tonight it was, I guess, very clear to me that she was playing very well and I didn't do enough and play well enough and I got beaten. There is still room to improve, and I've got a few days to do that.

"Look, three good matches is good. Of course you want more and you want to do better, but sitting here yesterday having won two and going into a third match, it's really good preparation for me. I've had a lot of tennis under my belt, which is a really good thing.

"Yeah, I can now go to Melbourne with probably a bit more confidence than I've had in previous years [but], obviously, there is still a lot to be done."

Puig burst into tears after the match, admitting she was overwhelmed by what she had managed to accomplish, reaching the semi-finals from the qualifying stage.

"I've been working so hard on every aspect of my game," Puig said.

"That's why I got a bit emotional after this win. It was a tough pre-season for me. It was a difficult year for me last year so it's really nice to see some of my best tennis so early in the season. I'm just really excited for what is to come.

"I'm definitely going to enjoy the win right now. It's a surreal feeling to pass the qualies and be in the semis. I'm just going to focus on that and get ready for tomorrow."