Ravi: R Ashwin playing - clever move or should have been playing since game one?

Bhuvneshwar Kumar with the new ball and South Africa off the mark courtesy of a wide down the leg side.

Struggles with his line first up but a chingwag with captain Kohli, who trundles over from mid-off to have a word, and it's much better from the seamer. Good length, angling in.

We're just moments away as de Kock and Amla skip to the middle. The beefeaters drumming away as they have been all tournament.

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The players line up and it's time for the anthems. South Africa up first, eyes closed as they belt it out at the top of their voices, in front of the backdrop of a sunny Oval. India next, slightly calmer but just as focused, followed by whoops from the crowd. Big support for India.

Isa Guha
Ex-England seamer on BBC Test Match Special

India missed Ashwin in the last game. He has got so much in his armoury and he is one of the most skilled bowlers in the world.

So one change each in this winner takes all game. For South Africa, all-rounder Andile Phehlukwayo comes in for the out-of-sorts Wayne Parnell.

India have gone for a spin option as Ravichandran Ashwin makes his first appearance in this tournament, coming in for Umesh Yadav.

The Indian fans roared and cheered when Ashwin's name was read out.

India: Rohit Sharma, Shikhar Dhawan, Virat Kohli (capt), Yuvraj Singh, MS Dhoni (wk), Hardik Pandya, Kedhar Jadhav, RA Jadeja, Bhuvneshwar Kumar, Ravichandran Ashwin, Jaspreet Bumrah.

South Africa: Quinton de Kock (wk), Hashim Amla, Faf du Plessis, AB de Villiers (capt), David Miller, JP Duminy, Chris Morris, Kagiso Rabada, Andile Phehlukwayo, Morne Morkel, Imran Tahir.

Umpires: Aleem Dar & Paul Reiffel.TV umpire: Richard Illingworth; match referee: David Boon.

With one upset in Group B out of the way, it was Sri Lanka's turn to stun India on Thursday.

In what was one of the classic run chases of recent memory, they successfully overcame India's total of 322 at The Oval to throw the group wide open.

The Pakistan team that turned up at Edgbaston to face South Africa on Wednesday must have been a different side to the one that got steamrolled by India. They must have been!

The rejuvenated players restricted South Africa to just 219-8 and then, with the aid of the DLS, managed to stay above the par score when rain halted proceedings.

Image source, Getty Images

After South Africa dominated Sri Lanka in their opening tie and India thrashed Pakistan, these two teams looked odds on to qualify for the semi-final.

But Sri Lanka and Pakistan had other ideas.

South Africa captain AB de Villiers: "I'm pretty happy batting first. We've seen some good scoring here. It's about good communication - to understand what's a good score.

"He's a good man and we get on very well, but we're both very competitive. There's a lot of pride and passion in both teams."

What's this then? Not a drop of rain to be seen at The Oval.

India captain Virat Kohli: "Teams have been chasing really well. When you bat second you know exactly what we need to do. It takes that stress out of it for us.

"We have batted pretty well in both the games - not many teams have got 320. But we couldn't defend it in the last game (against Sri Lanka)."

Time for the toss .... Virat Kohli has called it correctly and will field first.

Image source, Getty Images

Good morning and welcome to what essentially is a quarter-final tie, as the reigning champions play the world number one.

This one is simple - if India win, they qualify for the semis. If South Africa win, they qualify for the semis. The loser will be heading back home via Heathrow.

Whether you're on your phone, tablet, desktop or any other device, just relax and enjoy some high quality cricket.

Image source, Getty Images