Spain coach Vicente Del Bosque has urged his side to treat Tuesday's friendly with Chile in Geneva seriously - or suffer the consequences.
The world and European champions all but booked their place in next year's World Cup in Brazil by beating Finland 2-0 on Friday, meaning they need just one win from the next two games - against Belarus and Georgia next month - to qualify.
Del Bosque expects Chile to be tough opponents, but explained that a number of players who featured in Helsinki would be handed a rest, allowing other players to face Jorge Sampaoli's side.
"We either take Chile seriously or we will suffer, because they compete to the highest level and are always looking to attack," said Del Bosque.
"They have always been a very physical side when we've played them.
"We are going to use the occasion to allow everyone to participate and use the game as preparation for the matches with Belarus and Georgia next month."
The coach faces a selection headache in midfield, as both Real Madrid's Isco and Manchester City's David Silva were sent home due to an ankle injury and a muscular problem, respectively.
"Silva joined the squad with a knock to the thigh that he had while playing for Manchester City," said the coach.
"Yesterday (Sunday) he completed training fine but then felt some pain and it seems like he has a slight groin strain. But he wanted to play."
Those absences meant a 21-man squad travelled to Geneva. Arsenal's Santi Cazorla, who came on as a substitute against Finland, is expected to start as is Manchester City midfielder Javi Garcia, who played no part in the match in Helsinki.
Del Bosque said of his selection: "We will make changes in every position."
If the coach keeps to his word, Real Madrid centre-back Nacho Fernandez could also be given his Spain debut, while Tottenham striker Roberto Soldado or Manchester City's Alvaro Negredo will replace David Villa in attack.
Arsenal's Nacho Monreal is likely to come in for Barcelona's Jordi Alba, who got the opening goal in Helsinki and played the 90 minutes.
Goalkeeper Iker Casillas, who played the full 90 minutes against Finland despite not yet featuring for Real Madrid this season, is set to watch the game from the bench as Del Bosque revealed that Victor Valdes and Pepe Reina would both play against Chile.
"Tomorrow the two goalkeepers that didn't play against Finland will get a chance," he said.
"Any decision we take will always create a debate but we accept that naturally, and after tomorrow the debate will roll on. We take decisions with a level head and work how we want to. We have three excellent goalkeepers and we would happily accept any of them playing."