The team says Lee won't practice this week, and barring significant improvement, won't make the trip to the West Coast.
Lee caught eight passes for 73 yards in the first two games. He missed Sunday's 44-17 loss to Indianapolis with a right hamstring injury.
The Jaguars (0-3) have six other receivers on the 53-man roster: Cecil Shorts III, Mike Brown, Allen Robinson, Allen Hurns, Tavarres King and Kerry Taylor. They also have Ace Sanders on the suspended list.
Jacksonville likely will cut one to make room for an extra safety to replace backup Chris Prosinski, who will miss two to four weeks with an elbow injury.
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