The early goings were anything but easy - Larsson was up a break three times in the first set, including serving for the set at 5-4 and 6-5 - but the No.2-seeded Azarenka eventually squeaked the 72-minute set out in a tie-break and only picked up steam from there, closing it out shortly afterwards, 76(2) 62.
"She played really well," Azarenka said. "I can't say I was surprised by that, but she really went for her shots today. With these conditions, the ball bounces a lot higher, which suits her. It took me a little bit of time to adapt and find my range and my hitting zone. But she's really a very talented player."
With the heat soaring, players have been struggling - but Azarenka seems to have soared through it.
"Those conditions aren't easy, but you can't escape those, and it's the same for everybody. You just have to adapt to it and try to do the best things to prepare for those conditions. I feel pretty good.
"I went to practice afterwards, so I'm okay."
"The first set I managed to keep my head cool," Wozniacki said. "Every time in the changeovers, ice bags, ice towels, everything - then in the second set I could feel they were starting to heat up even more. I put the bottle down on the court and it started melting a little bit underneath, the plastic, so you knew it was warm. But it was warm for both of us, and it was great to finish the match off in two sets.
"I just had an ice bath now - yeah, I could go out and play another two sets now!"
Wozniacki was actually down a break early in the second set but knew it was important to close well.
"A match will always go up and down. For me it was important to just close it out as quickly as possible. Going down a break in the second set, I wasn't too pleased with myself - I was just like, 'Okay, try to keep the focus. Try and take one ball at a time and try and attack a little bit more out there.'
"Because once she gets time we'll have long rallies and it won't be too much fun."
And Wozniacki's advice for the heat? "Drink a lot of water, take a lot of salt, eat plenty and recover. I got an ice bath after my match because it's important for the body to be fully fit for the next round."