This already feels ominous for USA as Nosthush Kenjige's first over goes for 11 including back-to-back fours from Quinton de Kock, who has raced on to 34 from 14 deliveries.

SA 45-1published at 4 overs

4 overs

This is brutal hitting from Quinton de Kock as he mullers poor Jessy Singh for two sixes over deep square leg to make it 28 runs off the over.

These are relatively small boundaries but they were still two huge heaves from the South Africa opener.

Suddenly the match has a different complexion.

Aatif Nawaz
BBC Test Match Special commentator on BBC Sounds

A little bit of shortness and Quinton de Kock pounced on it. One of the finest in this format.

SA 33-1published at 3.4 overs

3.4 overs

Well, the USA have poked the beast.

New bowler Jessy Singh is smacked for four by Aiden Markram and Quinton de Kock.

Another short ball is clubbed away for six by De Kock - but Singh had overstepped!

Free hit coming up...

South Africa have now lost 12 wickets in the powerplay this tournament, averaging just 26 before the start of this match.

Skipper Aiden Markram strides out to the middle with his side in a bit of a hole again.

Peter Della Penna
Test Match Special commentator on BBC Sounds

Image source, Getty Images

A clever ball, Netravalkar has been such a catalyst for team USA. He used that lack of pace against Hendricks.

Aatif Nawaz
BBC Test Match Special commentator on BBC Sounds

What a shot from Hendricks. It had the distance to go all the way. This is more like it from South Africa.

SA 13-0published at 2 overs

2 overs

Shot.

Ali Khan is a little quicker than Netravalkar but he struggles with his line and length in his first over.

After a couple of sighters Reeza Hendricks has enough and smashes the ball on the up over the covers for six.

Peter Della Penna
Test Match Special commentator on BBC Sounds

This is the hallmark of Saurabh Netravalkar's game. His nagging accuracy has made him so successful for the USA. He's very authentic.

Image source, Getty Images

A solid start from Saurabh Netravalkar.

After conceding a single first ball he then bowls a beauty that goes across right-hander Reeza Hendricks before shaping away and beating the outside edge.

Netravalkar then overpitches slightly allowing Hendricks to drive for two.

This looks a fairly true surface, meaning Netravalkar will have to maintain his accuracy as he does not possess fearsome pace.

Quinton de Kock and Reeza Hendricks will open for South Africa.

Part-time cricketer Saurabh Netravalkar - who had to book holiday to play in this tournament - will bowl first for USA.

He has four wickets to his name so far - including Virat Kohli and Rohit Sharma.

After two stirring renditions of the respective national anthems we are ready to go. The USA team in particular looked pumped.

Image source, Getty Images

Before the action starts, I need to remind you that England's opening Super 8s match against West Indies takes place tonight at 01:30 BST and BBC Sport has you covered.

There will be ball-by-ball commentary on BBC Sounds and BBC Radio 5 Sports Extra. That commentary, plus live text updates and in-play video clips, will be available right here on the BBC Sport website and app.

Before and after every England game there will be a Test Match Special podcast available on BBC Sounds.

You will also be able to follow regular coverage on the BBC Cricket Instagram, external, and WhatsApp, external accounts.

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The good news is this match should not be hindered by the weather. There is plenty of white cloud scattered across the blue sky but it does not look too threatening, with a strong breeze billowing across the ground.

The legendary Sir Curtly Ambrose, who has an end named after him at the Sir Vivian Richards Stadium, has just walked out to the middle with the World Cup trophy. He still looks like he could bowl a few fearsome deliveries, even at 60.

USA have lit up this tournament so far. It is fair to say most observers would have predicted Pakistan to have progressed from Group A, but it is the co-hosts who progress to the knockout stages for the first time.

They opened the tournament with a thrilling win over Canada, before an equally dramatic super over victory against Pakistan. They gave India a scare before eventually succumbing. Their qualification in second place was confirmed after their final fixture against Ireland was washed out.

South Africa finished top of Group D with a 100% record, though that included narrow wins over Nepal and Bangladesh by one run and four runs respectively. They were also 12-4 against the Netherlands before eventually chasing down 104.

United States: Shayan Jahangir, Steven Taylor, Andries Gous (wk), Aaron Jones (captain), Nitish Kumar, Corey Anderson, Harmeet Singh, Jessy Singh, Nosthush Kenjige, Saurabh Netravalkar, Ali Khan.

South Africa: Quinton de Kock (wk), Reeza Hendricks, Aiden Markram (captain), Heinrich Klaasen, David Miller, Tristan Stubbs, Marco Jansen, Keshav Maharaj, Anrich Nortje, Kagiso Rabada, Tabraiz Shamsi.

South Africa captain Aiden Markram: "The pitch doesn't look too bad. We weren't sure what to do from a toss point of view. We would have leant towards bowling but the pitches here in the Caribbean can dry and turn later so we are not too bothered.

"We have gone with the extra spinner today. Keshav Maharaj comes in for Ottneil Baartman, completely based on conditions. They fully understand the situation and feel it gives us the best chance."

USA captain Aaron Jones: "I think it's going to be a good wicket, but if the seamers are going to get anything from it it's going to be early on.

"We're going with the extra spinner today. Maybe a little extra bounce, I don't think it's going to be too different from Dallas."

Image source, Getty Images

Monank Patel is still injured so Aaron Jones will skipper the USA side once more. His first job is to win the toss and elect to bowl first.