"This decision was made under the Pac-12's football game cancellation policy due to Washington State not having the minimum number of scholarship players available for the game as a result of a number of positive football student-athlete COVID-19 cases and resulting isolation of additional football student-athletes under contact tracing protocols," the Pac-12 said in a statement.
Washington State athletic director Pat Chun said the school has nine football players in COVID-19 protocols and that four players had to be put into the protocol Friday morning, leading to the cancellation of the game.
Chun said as of last weekend, the Cougars had no players in their COVID-19 protocols and that the first positive test came early in the week. The four positives Friday morning kept the Cougars from reaching the Pac-12 mandate of 53 scholarship players available. Among the players who tested positive is quarterback Jayden de Laura.
The cancellation will result in a no contest and is the second Pac-12 cancellation this week, after the Arizona State-Colorado game was called off on Sunday.
In a statement after the announcement, Chun said everyone in the program is "saddened for not only our student-athletes, coaches and staff, but those within the Stanford program who have worked so hard preparing for this weekend."
Stanford says it explored options for a replacement opponent but doesn't expect to find one and will turn its attention to its next scheduled game, against Cal.
Chun said it was too early to know whether next Friday's Apple Cup against rival Washington will be played as scheduled. He said figuring out the situation around the Apple Cup would begin Sunday.
"We're going to get through tomorrow as planned and come Sunday we'll start making our daily assessments about where our roster is at and where we're at with everything related to trying to field a team on Friday," Chun said.
The Associated Press contributed to this report.