Croatia midfielder Luka Modric believes his team's 2-0 victory over Nigeria on Saturday turned up the heat on Group D favourites Argentina.
Modric scored a second-half penalty to secure the win after Croatia went ahead through a first-half own goal by Nigeria midfielder Oghenekaro Etebo.
The result left the European side top of the group ahead of Iceland and Argentina, who drew 1-1 draw earlier in the day.
Crotia face Argentina next on Thursday in Nizhny Novgorod, and Modric said their respective table positions gives his side an edge.
"They [Argentina] have quality but this win will boost our confidence and I hope we can play well against them," Modric told reporters.
"It is going to be a difficult match. Maybe against the favourites in our group... but they will have to play for a win because of the scoreline today that they never expected."
With Argentina talisman missing his own penalty attempt earlier in the day, Modric was asked if he was nervous before his own spot kick. And though the man of the match denied any butterflies, he was certainly relieved afterwards.
"I wasn't [nervous]. I was focused on scoring. Thank God that I scored," he said. "Nothing more to say about that really."
Croatia had taken the lead through an own goal, and so Modric's penalty was his side's first shot on target in the game -- and the only one until Mateo Kovacic put in a soft shot in the 92nd minute.
But Croatia coach Zlatko Dalic wasn't worried and shrugged off the fact that both the team's scoring opportunities resulted from set pieces.
"A win is a win. Corners and penalties are part of football," he said. "What is important is that you score. There was luck there but we earned it. We want to be more attacking but we are not going to split hairs about how we scored.
"There's still much work to be done to emerge from the group but these three points are extremely important. We can't let our guard down. Nothing is over. We have to now think of Argentina."