Donovan will be assigned to the Sabres' American Hockey League affiliate in Rochester if he clears waivers Wednesday. The three-year NHL veteran was a healthy scratch for Buffalo's first three games. He signed with the Sabres in free agency in July.
Guhle was re-assigned to Prince Albert of the Western Hockey League after recovering from an upper-body injury sustained in a preseason game against Toronto two weeks ago. The 18-year-old was Buffalo's second-round pick in the June draft.
The Sabres (1-2) are coming off a 4-2 win over Columbus on Monday. They open a two-game trip at Florida on Thursday night.