Swiatek blasts Poland past France and into final of United Cup
Hurkacz, at a career-high nine in the world, defeated left-hander Adrian Mannarino 6-3, 7-5 in Sydney before world number one Swiatek toppled Caroline Garcia 4-6, 6-1, 6-1.
They will play either Alexander Zverev's Germany or hosts Australia in Sunday's mixed teams competition decider in the lead-up to the Australian Open.
It is the first final for Poland, who lost at the semi-final stage last year to eventual champions the United States.
"I'm happy that I came back and I didn't make so many mistakes as in the first set," Swiatek said. "For sure, Caro was putting pressure as usual, so I'm happy that we're through to the final.
"Sometimes it's a bit hard to point (to) one thing that changed (after the first set). I just feel like I needed to calm down a little bit and not rush it," she added.
Garcia was France's saviour in their 2-1 win over Norway in the quarter-finals, coming through a titanic struggle against unheralded Malene Helgo, then backing up to win in mixed doubles.
She again displayed her fighting spirit in breaking Swiatek for a 4-3 lead and taking the first set in 43 minutes.
But that was as good as it got for the world number 20, who folded as Swiatek moved through the gears to dominate the rest of the match
Swiatek grabbed the momentum back in the second set, surging to a 5-0 lead before converting her third set point at 5-1.
A break to love in the opening game of the deciding set deflated Garcia, with Swiatek largely untroubled as she raced to the finish line.
A steady Hurkacz played well in the critical moments and held serve with few problems to close out his match in one hour and 41 minutes.
"I think definitely today was a real battle," said Hurkacz, who won the Shanghai Masters last year and also tasted victory at Marseille.
"Adrian was playing really, really tricky shots and it's difficult to play against.
"So I was just battling for every single point, and I think mentally I was able to stay in the present, stay positive before each point and I think I was also really resilient today."
