Roger Federer responds to 'crazy' Iga Swiatek moment at United Cup

Roger Federer has joined tennis fans in marvelling over a ridiculous winner from Iga Swiatek at the United Cup on Sunday night. Swiatek teamed with Hubert Hurkacz for a mixed doubles victory that gave Poland a 4-1 win over Kazakhstan.

Hurkacz had earlier claimed a 7-6 (10-8) 4-6 6-3 win over Alexander Bublik before Magda Linette gave the Poles an unassailable 3-1 lead with a 6-2 6-1 victory over Zhibek Kulambayeva. Swiatek and Hurkacz then sealed the 4-1 result with a 6-3 6-4 triumph over Grigoriy Lomakin and Zhibek Kulambayeva.

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During the mixed doubles match, Swiatek produced what will go down as one of the shots of the year (already). Leading 3-2 in the first set, the women's World No.1 hit an extraordinary winner around the net post after being forced wide by a volley from Lomakin.

Swiatek's ball travelled in between the net post and umpire's chair and landed just inside the doubles line. The remarkable shot left fans and commentators in awe.

"What a shot from Swiatek," one commentators said. "Quite incredible. One of the shots of the tournament."

Another added: "That was absolutely amazing. That was incredible. Unbelievable shot."

Swiatek took to Twitter later on Sunday night to ask Federer if he approved. Federer, who has produced one or two similar shots in his time, responded: "That was crazy" with four 'mind blown' emojis.

Casper Ruud in impressive showing at United Cup

Meanwhile, Casper Ruud's tune-up for the Australian Open has begun in impressive fashion, while Petra Kvitova sealed a first United Cup victory for the Czech Republic by beating Germany's Laura Siegemund.

Kvitova's 6-4 6-2 win gave her country an unassailable 3-0 lead, securing the tie after German star Alexander Zverev was upset by Jiri Lehecka in his comeback from injury a day earlier. Germany won the second men's singles rubber and the mixed doubles, but the Czechs walked away with a 3-2 victory.

In Brisbane, World No.3 Ruud fought to keep Norway alive by beating Thiago Monteiro of Brazil 6-3 6-2. After an ankle injury kept him out of last year's Australian Open, Ruud made the final at both the French and US Opens to peak at No.2 in the world.

"It's always refreshing waking up on January 1. I always feel very motivated coming down here to Australia," he said. "Last year was a bit unfortunate, so I'm very eager to have a good start to the season and this is the perfect way to start."

Brazil went on to win the tie 4-1, with Laura Pigossi beating Ulrikke Eikeri 6-3 6-4 in the women's singles rubber, and Brazil also winning the mixed doubles. Croatia also won their tie against Argentina.

Petra Martic got the job done in the first rubber of the night for Croatia, taking own Nadia Podoroska 6-2 4-6 6-1 to give her side a 3-0 advantage. Croatia went on to inflict Argentina's second 5-0 loss after they had already been whitewashed by France.

Australia and Spain will do battle on Monday night in a dead tie after Great Britain secured their place in the next round following victories over both countries. Rafa Nadal is scheduled to take on Alex de Minaur in what shapes as a blockbuster showdown ahead of the Australian Open.

with AAP

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