Montevideo - Uruguay's Soccer World Cup Group A match against hosts South Africa will be decisive for their hopes of progressing to the knockout rounds, coach Oscar Washington Tabarez said.
The Uruguayans, who open against France in Cape Town on June 11, meet South Africa in their second game in Pretoria five days later.
"The first match is the most important because it is the first to receive all the affects of the (teams') preparations, the one that will leave a footmark for everything that follows," Tabarez said.
"But the decisive match is the second," Tabarez told the daily Ultimas Noticias in an interview published on Monday.
"Even winning the first match, the second is the match of confirmation or the return. We have to focus our minds and prepare well to try and play well in that match."
Tabarez will name his provisional squad of 30 on May 11.
The tournament opens with South Africa's match against Mexico in Johannesburg on June 11.