Paraguay will attempt to reach their first ever World Cup quarter-final inspired by the plight of team-mate Salvador Cabanas, the striker still recovering after being shot in the head in a Mexico City bar in January, according to Sunderland midfielder Cristian Riveros.

Though doctors say the 29-year-old has made a “tremendous” recovery and Riveros insists he is “doing well”, it is not yet known whether the player, who still has a bullet lodged in his skull after surgeons ruled an operation to remove it was too risky, will be able to play again.

Gerardo Martino’s side have remained in constant contact with the Club America striker, calling him as a group on several occasions, and Riveros believes his troubles give Paraguay extra motivation to emerge from their last 16 tie with Japan.

“The results here suggest that we have not missed him as a player, though I am sure he would have been welcomed as an extra attacker by the coach” said Riveros. “But we have definitely missed him as a person.

“We have all got together in the room at the hotel to call him and find out how he is doing. He is very well, very calm, and making a good recovery. There is no doubt that whatever we do in this tournament is with him in our minds.”

Should Paraguay overcome Takeshi Okada’s team, they will join four fellow South American nations in the last eight of the tournament. Had Chile not faced Brazil in the last 16, all five may have made it to the final week of the competition.

Though Martino insists there is no great secret to the region’s success, the Argentine does concede an elongated qualifying campaign presents representatives with a greater chance to hone a team.

“We all arrived well-prepared and in good form,” he said. “Not just Argentina and Brazil, who are historically successful in these tournaments, but ourselves, Chile and Uruguay too.

“The 10-team qualification group does present us with completely different problems than those experienced in Europe, Africa and Asia, if you compare the continents. The level of competition we face is much higher.”