St. Brown is set to enter his second NFL season after registering 21 receptions for 328 yards and no touchdowns as a rookie sixth-round pick out of Notre Dame in 2018.
Poor field conditions at Investors Group Field forced the Packers and Raiders to play on a modified 80-yard field Thursday. The issues were a result of the field goal uprights leaving a divot in each end zone due to the placement of the uprights for CFL games.
As a result, Packers head coach Matt LaFleur sat 33 players, including most of the team's biggest stars.
With Green Bay opting against adding a veteran receiver to replace Randall Cobb, who signed with the Dallas Cowboys in free agency, St. Brown was expected to vie for a starting job across from Pro Bowler Davante Adams.
Since St. Brown is expected to miss up to a month to start the regular season, the No. 2 receiver battle appears to be down to Marquez Valdes-Scantling and Geronimo Allison, although Jake Kumerow, J'Mon Moore and Trevor Davis have an outside chance to figure into the mix as well.
Like St. Brown, Valdes-Scantling was a rookie last season. He appeared in all 16 games and made 10 starts, finishing with 38 grabs for 581 yards and two touchdowns.
The 25-year-old Allison is more experienced but has struggled to remain on the field, as a concussion and groin injury cost him all but five games last season. He was productive when healthy, though, with 20 receptions for 303 yards and two touchdowns in those five contests.
Look for Adams, Valdes-Scantling, Allison, tight end Jimmy Graham and running back Aaron Jones to be the primary options for quarterback Aaron Rodgers in the passing game while St. Brown is on the mend.