The second seed came into the tournament buoyed by the biggest title of her career at the WTA Finals to end 2017 and, after her tremendous recovery to beat Jana Fett in the second round in Melbourne, has looked like a woman on a mission.
Wozniacki won the first seven games against Suarez Navarro, unseeded at this tournament but a former top-10 player, before the Spaniard battled back.
Suarez Navarro had a chance to lead 5-2 with a double break in the second set but Wozniacki fought back to level and then missed a match point at 5-4. It looked like it might prove very costly when Suarez Navarro claimed the tie-break but Wozniacki was the stronger in the decider.
It is the Dane’s first semi-final in Melbourne since 2011, and she said: “I knew it wasn’t going to be that easy.
“A lot of games in the first set were very close. In the second set I had the chance to close it out, I didn’t do it and that was very disappointing but I was proud that I managed to stay cool and finish it off in the third set.”
Next Wozniacki will face unseeded Belgian Elise Mertens, who took full advantage of fourth seed Elina Svitolina’s fitness problems to win 6-4 6-0 and race into her first grand semi-final.
“She’s had an amazing start to the year, I think she’s undefeated,” said Wozniacki.
“It’s going to be tough one but I’m excited for it.
“Another semi-final here, it’s exciting.”
Mertens, 22, was not ranked high enough to get into the main draw 12 months ago but currently stands at 37 and is set to break into the top 20 by virtue of making the last four.
Mertens is the first Belgian player to reach the semi-finals here since former champion Kim Clijsters, at whose academy she trains, in 2011. Addressing Clijsters, who was watching back home in the middle of the night, Mertens said: “I’m trying to be in your footsteps.”
Despite her lofty ranking, Svitolina was also looking to make her first slam semi-final but instead fell to her fourth quarter-final loss. She revealed after the match that she has been battling a hip problem all tournament.
“Today was very tough for me physically,” she said. “I was not ready to produce a good level of tennis. She’s a great player, she has a good level. I couldn’t match it.”