Fans celebrate in downtown Montevideo at the end of the Uruguay vs South Korea match on Saturday. ((Pablo Porciuncula/AFP/Getty Images) )

The smallest remaining country at the World Cup is into the quarter-finals, and whatever Uruguay lacks in quantity of population it more than makes up in the quality of its fans.

Uruguay won the World Cup in 1930 and 1950, but the country has struggled to make an impact since, with a round of 16 exit in 1990 its best recent result before Saturday's 2-1 win over South Korea.

The South American country will face Ghana in a quarter-final July 2, the first time in 40 years Uruguay has reached that stage of the tournament. The win over South Korea sparked huge celebrations in Uruguay.

"We are starting to receive SMSs and calls and we are absolutely delighted," Uruguay coach Oscar Tabarez said. "There are only 3.5 million inhabitants and it's been a long time since we had something like this."

Luis Suarez scored twice Saturday, and the forward described his winning goal in the 80th minute as "the most important" of his football career.

"What came to mind is the people, my wife, my daughter, they are always behind me," Suarez added. "And also to the people of Uruguay.

"They have backed us in the good times and the bad times."

Suarez, who is among six players tied for the tournament lead with three goals each, said his team has a fighting spirit.

"We have been dreaming since this tournament started," Suarez said. "Some teams start out as favourites.

"My side is ready to fight hard for wonderful things. We have to live the emotions and what we are feeling in every match."

Diego Perez, who plays for French club Monaco, said "it's a beautiful moment and a unique feeling in our country."

"We know that in our country they're all out in the streets," Perez said. "We have a great history, but we're only a small country.

"Our heads are in the right place."