Croatia survived missing a penalty to claim a 1-0 win over Uruguay in Group F, with Ante Rebic's effort just before half-time settling the game.
Marko Livaja missed an earlier penalty and, despite an improved Uruguay after the break, managed to hold on in a largely equal battle between two strong, but technical, sides.
It was the first competitive game between these teams at any level, but neither side was able to secure any meaningful spells of possession early-on. However, with Ante Rebic and Marko Pjaca working the flanks of a Croatian front three, they soon began to create in-roads.
It was through Pjaca that the first chance materialised, with the Lokomotiva Zagreb starlet beating Gianni Rodriguez on the byline and forcing the Uruguayan defence to hack away his dangerous low cross.
The South Americans went close shortly after as Jose Gimenez rose at the back post to meet a deep free-kick, but could only find the side netting.
Los Charruas were given a huge let off midway through the first-half when Croatia spurned the opportunity to score from 12 yards. A superb ball from inside the Croatian half found Dario Canadija in behind the defence, with Gaston Silva clipping his heels. However, Marko Livaja's effort hit the inside of the post, and then goalkeeper Guillermo De Amores, before being cleared.
Croatia still managed to go in ahead at the break though, this time it was Rebic making the difference. Livaja was fortunate to see his forward pass deflect off new Manchester United signing Guillermo Varela right into the path of Rebic on the edge of the area. He cut away from goal, before firing back across into the left corner beyond De Amores' despairing dive.
Uruguay almost hit back straight after the break, however, as Diego Rolan's glancing, diving header forces a sublime one-handed save out of Oliver Zelenika. From there Juan Verzeri's side slowly began to turn the screw.
Their next opportunity came in the form of a spectacular overhead-kick from Giorgian De Arrascaeta. Jozo Simunovic sloppily conceded possession on the edge of his area, leading to Diego Rolan's far-post cross, but Arrascaeta could not keep his effort down.
They went even closer minutes later. Great work by Diego Laxalt saw him wriggle free on the by-line and cut the ball back to substitute Nicolas Lopez, but he hit the post from six-yards when he should have done better.