The Sixers' one-run win over Adelaide on Sunday meant they finished second on the ladder, giving them a home final on Thursday.
While top side Hobart are favourites to win their first title, the Sixers are the form side going into this week's finals series with four wins from their last five completed games.
None of this looked likely for Sydney on November 20.
Meg Lanning put on a batting masterclass and scored 135 as the Melbourne Stars amassed 4-219 - the third-highest score in competition history.
No Sixers player managed double figures as they were blasted out for 42. It was the second-biggest win in WBBL history.
But in fairness, a team featuring Ellyse Perry, Sophia Dunkley, Alyssa Healy and Ash Gardner was never going to take that humiliation lying down.
The Sixers have lost only once since.
"This season has ... shown that we've won those scrappy games, which gives a lot of character and fight," captain Gardner said of their overall form.
"It's also being able to win those small moments ... which we've been on both sides of."
They are now two wins away from becoming the first three-time WBBL champions.
"It's been quite a frustrating time. We had a lot of success through the early part of the Big Bash," Gardner said.
"We've played ok cricket, but just not consistent cricket."
Indeed, it was a near-run thing. The Sixers could have finished anywhere from second to fifth depending on Sunday's result.
It took Gardner's yorkers at the end to deny Adelaide.
"Bowling yorkers at the death is probably my go-to. When I execute, it is a really hard ball to try and get up and under," she said.
"I'm just glad it went the way it did for us.
"In those pressure moments, you just have to keep your cool. I would have hated to have known what my heart rate was through that last over."
Importantly, Perry and Dunkley will also take solid form into the finals as Sydney's star opening pair.
Perry's 111 on Sunday was her highest WBBL score and Dunkley, recruited with the No.1 draft pick, added 54.
"We picked her up for a reason. That was part of our list we felt like were lacking, having someone up the top who absolutely takes the game on," Gardner said of Dunkley.
"Dunks is never going to muck around at the top.
"Just the way they complement each other - Pez is more of a purist and then Dunks just opens up different areas of the ground.
"She's obviously a ripping human as well, so she's someone who fits in so seamlessly in any group."
The finals start on Tuesday when third-placed Perth host fourth side the Melbourne Stars at the WACA.
The winner will head to Sydney for Thursday's game and the winner of that clash will face the Hurricanes in Hobart on Saturday in the final.
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