2010 winners Spain will clash with hosts Russia on Sunday, while Croatia will take on Denmark in the two Round-of-16 matches.
The Spain-Russia game will be played at the Luzhniki Stadium in Moscow at 7:30 pm (IST) while the Croatia-Denmark game is scheduled at 11:30 pm at Nizhny Novgorod.
Spain drew two and won a game in the group stage while Russia have, so far, been good in front of their crowd.
Croatia is also in superb form following their wins over Argentina, Nigeria and Iceland in the group stage wile Denmark has won one and drew two. It may be mentioned here that the Danes are also on a national record unbeaten run of 18 games.
Uruguay and France will meet for a place in the semi-finals on Friday.