Marshall left Saturday's game against Utah with what appeared to be an ankle injury.
In the first four games of the season, Marshall had nine catches for 121 yards and two touchdowns. Marshall has also averaged 27.5 yards per kick return this season.
Last season marked Marshall's first year playing wide receiver for the Ducks after transitioning from running back. In 2014, he led Oregon with 47 receptions for 1,003 yards.
The Ducks (2-2) play at Colorado (3-1) on Saturday.
- Beth Maiman