The second-year forward had an appendectomy Friday at the Cleveland Clinic. The team said Saturday that Zeller is recovering in the hospital and no timetable has been set for his return.
It's been a tough start to the season for Zeller. He injured his hip last week after a fall in an intrasquad scrimmage and has missed Cleveland's first two exhibition games.
Drafted in the first round last year from North Carolina, Zeller averaged 7.9 points and 5.7 rebounds as a rookie.
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