Arizona Cardinals quarterback Drew Stanton may be lost for the rest of the season after the team reportedly discovered an infection this week which required arthroscopic surgery.

The infection, discovered Wednesday, was believed to have been caused by an outside medical procedure, the NFL Network reported Friday.

Arians said earlier in the week that he hoped Stanton would be ready for the playoffs after missing the final two regular-season games with a sprained knee. The Cardinals (11-4) have already clinched an NFC playoff spot.

According to the report, the development with the infection could be why Cardinals coach Bruce Arians decided to go back to Ryan Lindley over rookie Logan Thomas for Sunday’s game against the San Francisco 49ers. Arians originally was planning to bench Lindley in favor of Thomas.

Lindley has not thrown for a touchdown in 225 career pass attempts but has been intercepted eight times. He completed just 40.7 percent of his passes (22 of 54 for 246 yards and one interception) last week in the 35-6 loss to the Seattle Seahawks.

Thomas, a rookie fourth-round pick in the 2014 NFL Draft, is considered a project and has looked shaky during practice, The Arizona Republic reported.