Spain's second string players will aim to press their case for a place in the team for the knockout stages when they play Saudi Arabia today
With a place in the last 16 assured and top spot in Group H effectively in their pocket, coach Luis Aragones will rest several first-choice players this afternoon.
It was the substitutes who came to Spain's rescue against Tunisia on Monday, Raul scoring the equaliser and Cesc Fabregas and Joaquin helping tease open the defence.
Their performances showed how little there is to choose between the players and a strong performance could be rewarded with a place in the starting line-up.
"Everyone wants to play," Joaquin said.
"Even though we have already qualified it is still a World Cup match and I'm determined to make the most of the opportunity."
Leading striker Fernando Torres will be rested, while Raul and David Villa are likely to play 45 minutes each up front. Santiago Canizares will stand in for Iker Casillas in goal and Aragones will also field a new-look back four.
Victory against the Saudis would mean Spain qualify with a 100 per cent record in the group for the second time in a row and further strengthen their belief that this is their year.
"If we win our last game and finish on nine points then people will realise we mean business," said Torres.
Saudi Arabia coach Marcos Paqueta knows that anything other than an unlikely victory over Spain could spell the end of his short stint in charge of the national team.
The Brazilian was only recruited in December to replace Argentine Gabriel Calderon, who had guided the Sons of the Desert through the qualifying campaign in style.
Paqueta has vowed to fight on but will need an extraordinary improvement after his team imploded in a 4-0 loss to Ukraine, having thrown away victory against Tunisia in their opener.
He is unlikely to make sweeping changes, although needing a victory to have a chance of reaching the last 16 for the first time since 1994, he could start with veteran skipper Sami Al Jaber supporting Yassir Al Qahtani up front.
"We knew we had two difficult games against Ukraine and Spain, but in life you have to have hope in everything and be positive right to the end," said Paqueta.
Probable teams
Saudi Arabia (4-5-1): 1-Al Deayea; 2-Dokhi, 13-Sulaimani, 4-Al Montashari, 3-Tuker; 14-Al Khariri, 6-Al Ghamdi, 8-Noor, 9-Al Jaber, 16-Al Thaker; 20-Al Qahtani.
Spain (4-3-3): 19-Canizares; 2-Salgado, 20-Juanito, 4-Marchena, 12-Lopez; 6-Albelda, 13-Iniesta, 18-Fabregas; 17-Joaquin, 10-Reyes, 7-Raul.
Referee: Coffi Codjia (Benin).