According to Mike Spofford of Packers.com, it was a "precautionary" decision. He had previously been expected to play a "quarter or so" after sitting out the team's preseason opener against the Houston Texans on Aug. 8.
Rodgers has been durable throughout his career, though the 35-year-old has had two significant injuries that caused him to miss multiple games in a season.
In 2013, Rodgers broke his left collarbone during a game against the Chicago Bears that kept him out for seven games. Four years later, the two-time NFL MVP missed seven games after breaking his right collarbone against the Minnesota Vikings.
Last season was a mixed bag for Rodgers, who threw for 4,442 yards with 25 touchdowns and two interceptions. His completion percentage (62.3) was his lowest in a 16-game season since 2015.
The Packers hired Matt LaFleur as head coach during the offseason to get them back on track after back-to-back losing seasons.
Rodgers' absence figures to give DeShone Kizer a chance to see more time under center.