Russia boss Stanislav Cherchesov believes his side would've lost to Spain had they not embraced his defensive tactics.

The World Cup hosts progressed to the quarterfinals after beating Spain on penalties.

Playing with a back-five, Russia sat deep inside their own half and allowed Spain over 70 per cent possession throughout the match.

"They are better than us in many ways," Cherchesov told reporters. "So I don't believe we should risk going forward. I believe we chose the best tactic.

"I believe we should have attacked at a better level coming from the defence but had we chosen a different tactic we would not have fared as well and had we had four defensemen i believe they would've attacked more.

"I believe the players have been victorious because they adhered to my strategy."