Reilly Opelka has won the first set 6-3 against Giovanni Mpetshi Perricard.

The American received more physio treatment on his right wrist at the change of ends but has given no indication he will retire.

Reilly Opelka has received on-court treatment from the tournament phyiso for what appears to be a right wrist concern.

This is worrying, as Opelka has had multiple wrist injuries that threatened to end his career.

A medical timeout was called and Opelka returned to the court.

Let’s hope this isn’t as serious as it appears to be.

Opelka is leading Giovanni Mpetshi Perricard 5-2 in the first set.

An early service break has given Reilly Opelka a 3-0 lead in the opening set against Giovanni Mpetshi Perricard.

The towering American — standing at 211cm — broke the rising French star in the second game.

Right … we’re trying to unpack what just happened in Sydney.

Meanwhile, Reilly Opelka — 24 hours after beating Novak Djokovic — is playing Giovanni Mpetshi Perricard in the Brisbane International semifinals.

The players are on the court warming up and we’ll update you throughout the match.

I don’t think I was the only person shocked at last night’s singles result in the men’s draw, when Reilly Opelka scored a stunning upset win over Novak Djokovic.

Djokovic didn’t do much wrong in truth, but he was blown away by the power and angles created by the largest man I’ve ever seen on a tennis court.

If you wanted to see what impact Djokovic had on Opelka during his lengthy injury breaks over the past couple of years, which is why his ranking of 293 is a real false position, read this.

Drama at Ken Rosewall Arena, with Czechia’s Tomáš Macháč suddenly retiring during his singles rubber against Taylor Fritz of the US.

With Fritz to serve for the second set at 6-5, Macháč abruptly indicated to the chair umpire he was withdrawing while pointing to his upper right leg.

In his on-court interview, Fritz said Macháč told him he was cramping.

Only minutes earlier, Macháč was berating himself and his team captain Daniel Vacek after he coughed up a 5-2 lead and multiple match points in the second set.

Having won the first set in a tie-break (7-4), Macháč had two match points on Fritz’s serve in the eighth game of the second.

Fritz held and eventually won four straight games.

The win gave the US an unassailable 2-0 advantage in the semifinal.

Earlier, Coco Gauff defeated Karolína Muchová 6-1, 6-4 to give the US a 1-0 lead.

The US will play Poland in Sunday’s final.

Aryna Sabalenka moves on to the final after a straight-sets victory over Russian teenager Mirra Andreeva.

Sabalenka won 6-3, 6-2 and will play Polina Kudermetova in Sunday’s final.

Eighth-seeded Andreeva may not have won a set against Sabalenka, but she did trouble the world number one.

She had eight break points during the match, however was unable to convert on any of them.

The 17-year-old has a bright future and she’ll be one to watch at the Australian Open when it begins in just over a week’s time.

Aryna Sabalenka’s experience is shining through as she gains a double break on Mirra Andreeva’s serve.

The US Open champion will serve for the match at 5-2 in the second set.

Aryna Sabalenka enjoys some breathing space in the second set of her semifinal against Mirra Andreeva.

The two-time defending Australian Open champion broke her opponent in the third game to lead 2-1.

A spot in the final against Polina Kudermetova is up for grabs in this evening’s match.

Czechia’s Tomáš Macháč is a set up against American Taylor Fritz in the second singles match in the United Cup semifinal in Sydney.

Macháč won a tie-break (7-4) in the first set to give himself an excellent chance of levelling the tie at 1-1.

Coco Gauff had earlier defeated Karolína Muchová 6-1, 6-4 in the opening singles rubber.

Aryna Sabalenka claims the first set against Mirra Andreeva, winning 6-3 after 52 minutes on court.

Andreeva showed her fighting qualities to save two set points in the ninth game.

She even had a break point to put the set back on serve.

The weather conditions are steamy inside Pat Rafter Arena, with Sabalenka opting to rub an ice pack over head during the change of ends.

Aryna Sabalenka gets a service break in the eighth game.

She had two break points in her possession but only needed one to claim a 5-3 lead over Mirra Andreeva.

An absorbing seventh game of the opening set, with Aryna Sabalenka holding to lead 4-3.

It was not without drama, as Mirra Andreeva snared a break point before Sabalenka eventually held.

Some of the rallies between these two have been extraordinary so far, with both producing punishing groundstrokes.

We mentioned Mirra Andreeva would be a stiff challenge for Aryna Sabalenka to overcome and she’s already proved that’s the case.

The young Russian put Sabalenka’s serve under immediate pressure, earning three break points in the opening game of the match.

Sabalenka saved each to hold, but the early signs are clear Andreeva is not intimidated by the world number one.

World number one Aryna Sabalenka is yet to drop a set in Brisbane, but she faces a stern test against Russian teenager Mirra Andreeva.

At 17, Andreeva has already reached the semifinals of a major following an inspired run at last year’s French Open.

She is ranked at a career-high 16 and is seeded eighth in Brisbane.

This promises to be an intriguing match-up.

Coco Gauff has completed her assignment by winning the opening singles rubber in the United Cup semis.

Gauff defeated Karolína Muchová 6-1, 6-4 to give the US a 1-0 lead over Czechia at Ken Rosewall Arena.

Service breaks were traded late in the second set, but Gauff already had one up her sleeve.

Taylor Fritz is up next against Tomáš Macháč.

That’s the official note from the tournament organisers.

Hopefully he’ll be OK to play in the Australian Open.

Coco Gauff is two games away from giving the US a 1-0 lead in its semifinal with Czechia.

Having won the first set 6-1 against Karolína Muchová, Gauff is up 4-2 in the second, with a break in hand.

She did have some trouble holding serve in the sixth game of the second set, with Muchová picking up break points.

But Gauff eventually held to move a step closer to victory.

So, there is a bit of a bottle neck of matches taking place this evening.

For one, Jiří Lehečka, who has just won the men’s singles semifinal, will have a couple of hours off before he plays in the men’s doubles semifinal with Jakub Menšík on Court 1.

Their opponents in that match will be Nicolas Jarry and Giovanni Mpetshi Perricard, the latter of whom will be playing in the other men’s semifinal tonight, which starts no earlier than 8:00pm.

That means he won’t be on court until close to 10:00pm.

The reason that doubles will be on Court 1 is because the women’s doubles final is tonight, which is going to feature Mirra Andreeva.

Andreeva, of course, is in action against Aryna Sabalenka in about 45 minutes.

Confused?

Good.

The first men’s finalist, Jiří Lehečka has been speaking after his win over Grigor Dimitrov.

“This is never the way how you want to finish a match,” Lehečka said.

“Obviously you just want to win, but not like that.

“Hopefully Grigor is fine. Hopefully he’ll be ready for Melbourne.

“I don’t know if it’s something serious or not. I just felt in the last two points he made, he couldn’t move.”

He said that he was very impressed with the level he played.

“The first set and the first half of the second was a good level. I think that we both played good tennis,” he said.

“In the first set I was a bit more solid in the game where I broke his serve, he made two mistakes at the net.

“Overall it was good tennis from my side. I was focusing on keeping the aggressive game style, going for the points, not to be scared to play aggressively. I think that it worked well.”