'Hard to put into words': Switzerland and Poland set up ultimate showdown in United Cup final

Team Poland takes a celebratory selfie after reaching the United Cup final. (Getty/Robert Prange)

Switzerland and Poland have won their semi-final ties in the United Cup against Belgium and the USA respectively, with both ties being decided in thrilling mixed doubles matches to set up a blockbuster showdown.

In the day session, Switzerland played Belgium in stifling heat, which peaked at 43 degrees at Sydney Olympic Park as the teams struggled, even with play moved half an hour earlier.

Belinda Bencic fought her way through a three-set epic against Elise Mertens before Zizou Bergs levelled the tie against Stan Wawrinka, despite the veteran taking the second set in a tiebreak and delighting the crowd with his trademark backhands.

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Bencic did not display the same dominance she had in Perth, but fought through the deciding set, with Wawrinka staying on the bench for the whole match to support her (an incredible effort, given he had to play his match less than 10 minutes after hers).

"I think today was really overcoming myself. It was a bit weird. You're still in the same tournament, you play semifinal, but it feels like a first-round match again because it's a different site. It's very special. It never happens normally in a normal tournament. I think it felt a little bit that way. I think I was just a little bit off, maybe for the whole match with myself, with my thoughts," said Bencic.

Wawrinka had shades of his brilliant peak in the second set, with his brilliant backhand and touch coming to the fore, but in the third set, fatigue set in as he was broken from 40-0 up to give Bergs the crucial lead in the match as he struggled to adapt to the Sydney conditions.

"I start to think a bit too much," said Wawrinka. "When you get a bit tired, of course was tough match for him, for me. He change a little bit. He went a little bit back. I start to doubt about myself and about the choice I wanted to make. That's when I start to stop moving well, start to not go through the ball. That's what happen.

"It was, of course, hot. It wasn't easy to adapt for sure because is not the same condition, is not the same Centre Court. Of course, they try maximum to make it equal, make it the some. But when you change city, when you change also with the roof indoor, it was for me a little bit difficult. At the beginning was a bit faster, flying a little bit more, so we had to adapt."

With the tie coming down to the mixed doubles, Switzerland fielded their unbeaten team of Bencic and Jakub Paul against Mertens and Bergs.

The Belgians then dominated the second set, as Bencic and Paul began to feel the heat before the Swiss team rebounded spectacularly, flying through the deciding tiebreak to seal a tight victory and book their spot in the final.

"Very proud of the team. Again, MVP, [Jakub Paul]. Well done. Belinda, show us again why you are a great champion was a tough one this morning, but you went through it," said Wawrinka.

"It's just amazing to see him play and how brave he is. He's taking stuff, he's on hands," said Bencic of Paul, who has been the revelation of the tournament.

The camaraderie of the Swiss team was notable, with Wawrinka staying to support Bencic through her whole match and Paul and Bencic watching the entirety of Wawrinka's match before the mixed doubles in stifling heat. The team attributed much of their success to the bond they have formed throughout this tournament.

"Well, I just have to say, I mean, Stan pushes me through in my singles, then he tries to push himself through in his singles, then he pushes us over the line in the mixed. I don't know what to say. It's just amazing. You can see how much you put your heart into it. Best captain," said Bencic.

"I think we just all really want this so much. You can feel it. You can see it. We really are a team. We feel that way. You can definitely feel it when you're playing. It's fully something that gives us the extra push and the extra motivation."

In the evening, Poland took on the USA, with Hubert Hurkacz cementing his position as a dark horse for the Australian Open with a 7-6, 7-6 win over Taylor Fritz.

"Pleased with my performance on the singles court, especially after quite a difficult match the day before with Alex," stated Hurkacz.

Coco Gauff and Iga Świątek then took to the court in the blockbuster match of the day. Some of the rallies at the start of the match were scintillating as the two players duelled from the baseline, with neither giving much away. However, Gauff took a lead midway through the first set and then dominated the early parts of the second set to take a 5-0 lead.

While Świątek fought back admirably, Gauff held her nerve to close out a 6-4 6-2 victory.

"For sure I feel like Coco has improved stuff. It's quite visible. The matches we played couple years back where most of them were kind of one-sided. I feel like that's it. She's also growing in age, more experienced as well," said Świątek.

"She's a top player for many years now, even though she started with she was, like, 16, much earlier than most of us do."

In the deciding mixed doubles, Gauff returned alongside Christian Harrison to take on the unbeaten duo of Katarzyna Kawa and Jan Zieliński, who were fresh off their victory against Australia.

The match was tight, with Team USA have chances in both sets, serving for the set twice but again, Zieliński was the hero, playing extraordinary mixed doubles with frequent gestures to the fired-up crowd to send Poland into the final.

"It's hard to put it into words. I mean, always said playing for your country, playing for your team, it's something special. It's bigger than just playing tournaments, winning all by yourself," said Zieliński.

"Ninety-nine per cent of the season is alone, we play for ourselves. For me these weeks where we play Davis Cup, Billie Jean King Cup for the women, this United Cup event, is a special week for me. I always cherish all the moments. Being able to help the team, put that one little brick from my side, help the team reach the finals, is an incredible feeling."

Zieliński has become arguably the go-to player on the ATP side for mixed doubles, which he credited to being more relaxed and loose on court.

"I started my mixed career 0-4 in slams. I was very, very close to retiring from mixed doubles completely. Then Su-Wei [Hsieh] came in the picture. She showed me a little bit different approach to mixed doubles, with a smile on the face, being more relaxed," he said.

"This is a very tricky game. There's a very different rhythm than in the real doubles or even singles. It's a very, very special game. You have to adjust. You have to know how to time yourself at the net, at the back. It often is about adjusting to the speed of the opponents because some are serving faster, slower. Some are playing singles, doubles, different combinations that you don't see every day. You can't really practice it."

The final will commence tonight with Świątek taking on Bencic before Hurkacz battles Wawrinka. If the tie goes to the mixed doubles, it would be safe to assume that Bencic and Paul will play Kawa and Zieliński for the title, which should be a great end to a strong edition of the United Cup.

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