The Liverpool goalkeeper appears set to take the place of Iker Casillas, whose status as number one has been questioned after a series of errors in his country's defeats to the Netherlands and Chile.
Those results saw Spain's title defence end at the group stages, but Reina's inclusion is likely to be one of many changes for Monday's dead-rubber match in Curitiba.
"(I will) look for all those who have come to participate in this World Cup," he said.
"I definitely won't be playing Xavi. He has a little muscular problem.
"Reina is likely to play, yes."
Reina himself added: "It is clear that we'd like to finish with dignity, with a victory.
"In football, the most beautiful thing is to win, and (on Monday) will be no different."
Del Bosque will also hand a 100th cap to Andres Iniesta - one of the central figures behind Spain's dominance of world football over the past six years.
"Yes, Iniesta will play the 100th game," he said.
"There are details that do not escape us."
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