World Cup hosts the West Indies, and South Africa, the team ranked number one in the world at the beginning of the tournament, go into Tuesday's World Cup Super Eights match at the Grenada National Stadium both knowing that a loss could end their chances of reaching the semi-finals.
South Africa's shock 67-run defeat against Bangladesh in Guyana on Saturday has dragged them closer to what could be a four-way battle for the final semi-final place along with England, the West Indies and Bangladesh, while Australia, New Zealand and Sri Lanka look likely to advance.
Meanwhile, the West Indies are by captain Brian Lara's admission, "in a crisis situation".
To be sure of reaching the semi-finals, both sides need to win all three of their remaining matches, although it is possible that two wins and a high net run-rate could be enough.
Graeme Smith, South Africa captain, admitted the defeat against Bangladesh had meant the loss of two points his team were banking on.
"It's a big loss for us," Smith said.
"It's still in our control and the next three games are important. We don't want to be relying on other people to get us through."
Lara said his team were physically drained by having four games on sandy outfields in ten days after his team's 113-run defeat by Sri Lanka in Guyana last Sunday, however they will face South Africa after a nine-day break.
Some West Indies players took time off before reassembling in Grenada and the team have been heavily criticised with Lara's captaincy singled out for ridicule.
Herschelle Gibbs, South African batsman, is under an injury cloud after leaving the field because of a calf strain during the Bangladesh match, while all-rounder Andrew Hall was rested because of what was described as a minor thigh strain.
South Africa will have a selection dilemma if Hall recovers, as his replacement Andre Nel took a career-best 5 for 45 against Bangladesh and was the only South African to perform to his best ability.
Adding to the uncertainty ahead of the big clash between the two teams is the state of the pitch in Grenada, after it was re-laid at the National Stadium which was rebuilt after the original Queen's Park ground was devastated by the hurricanes of 2004 and 2005.