South Africa will look to shed the "chokers" tag, while England, the perennial underachievers in one-day cricket, will be desperate to corner glory by entering the finals of the ICC Champions Trophy.
The two sides meet in what promises to be a high-voltage semifinal at The Oval, with plenty at stake.
"It's a massive game for both sides," England skipper Alastair Cook said. "We've got the opportunity to go into the final of an ICC competition, and it's such an exciting place for a player to be.
"We've almost played knock-out cricket throughout this Champions Trophy, but this is obviously one step towards the final, and we've come here to try and win the tournament. It's an amazing opportunity we've got tomorrow (Wednesday), and I think both sides will be excited."
South Africa have choked, unbelievably at times, when it has come to the big games, and AB De Villiers and co. will be desperate to prove their critics wrong by putting in a professional performance which will see them through to the final, where they will then face the winners of the second semi between Sri Lanka and India.
"We've had two big games, the last two games we played, and we didn't choke there," De Villiers said. "Obviously that's a good start. We owned up to it before. It's something that's been around for a while.
"I believe all teams choke in certain situations. It's just we somehow managed to get that tag behind our names. Unless we win this tournament, people will stay say you're chokers, so no matter what happens, it's something we've dealt with.
"I think we're very comfortable with it in the team. We know what we're capable as a team, we're in a very good space. We're not thinking of stuff like that. But even though in the same breath it's not something that really bothers us at the moment."
England will most likely not risk Graeme Swann, while Tim Bresnan, who is expecting a baby, could make way for Steven Finn.
South Africa again have doubts over the fitness of Dale Steyn, but De Villiers was reasonably confident his premier fast bowler would be passed fit to play the semifinal.
If rain interferes, as it invariably does in England, and a result is not possible, then England will go through to the final owing to the fact that they were winners of their group; therefore South Africa will be desperately hoping for some sun to come out for about seven hours or so come Wednesday.
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Expected lineups: England: Cook, Bell, Trott, Root, Morgan, Buttler, Bopara, Broad, Tredwell, Anderson, Finn.
South Africa: Ingram, Amla, De Villiers, Duminy, Du Plessis, Miller, McLaren, Peterson, Morris, Steyn, Tsotsobe.
