Croatia have taken maximum points from their opening game of the Under-20 World Cup against Uruguay, thanks to a first-half strike from Ante Rebic.
The result puts them second in Group F behind Uzbekistan following their 3-0 win over New Zealand.
Dinko Jelicic's men had the chance to take the lead from the spot in the 22nd minute, but Atalanta striker Marko Livaja smashed his kick off the woodwork.
However, Rebic found the net five minutes before half time with one of the few shots they had on goal in the first period.
The South Americans ploughed forward after the break, with Nicolas Lopez once again striking the frame of Oliver Zelenika's goal, but they could not find the crucial equaliser.
They will take on New Zealand in their next game, while Croatia face off against Uzbekistan.