Reports had suggested that the Spanish striker would be passed fit to take his place in the starting lineup.
However, coach Unai Emery has insisted that it would have been too much of a risk to gamble on the 26-year-old's fitness.
"He is eager to play and has the desire but from a medical position, it is better not to force the issue," Emery told reporters at a press conference.
"Tomorrow's game is very important but it would be a big loss if he could not play in the matches that follow."
Soldado is now expected to return in Thursday's Europa League tie against Atletico Madrid.