Croatia captain Luka Modric has insisted that his side must remain focused after reaching the World Cup knockout stages with a 3-0 defeat of Argentina.

Modric scored the pick of the goals from outside the box as his strike - sandwiched by efforts from Ante Rebic and Ivan Rakitic - put Croatia into the last 16 for the first time since 1998.

Real Madrid midfielder Modric told Sky Sports News that his teammates must not "get ahead" of themselves following their defeat of the two-time champions.

"Let's not be euphoric or get ahead of ourselves," the 32-year-old said. "Of course this win will boost our confidence for the next game, and we have shown we can create opportunities, but let's keep our feet firmly on the ground.

"Our team effort throughout [was the key] and particularly in the second half when we had more possession. In the first half when Argentina had the ball we cut off [Lionel] Messi and stopped him getting the ball.

"He is the most dangerous player. We created three clear chances which we missed. But in the second half it opened up and we deserved to win."

Croatia's final Group D game is against Iceland on Tuesday.