Croatia salvaged a 2-1 victory over Iceland in their final Group D match on Tuesday and qualified for the round of 16 as Group D winners. They will face Group C runners-up Denmark in Nizhny Novgorod on Sunday.

"We beat Iceland today, but we were lucky. Despite three wins [2-1 over Iceland, 3-0 over Argentina and 2-0 over Nigeria], it was extremely difficult to reach the knockout stage. There was not a single easy game, not a single easy victory. We can do better. We are surely the favorites to win the Denmark match. We know how to take on this team. However, the opponents should by no means be underestimated," Lovren told journalists.

The 2018 FIFA World Cup kicked off on June 14 and will continue until July 15, with the matches being played in 11 cities across Russia.