user: Question: Who was the outgoing manager that was replaced by Thomas von Heesen?
Columns: ['Team', 'Outgoing manager', 'Manner of departure', 'Date of vacancy', 'Replaced by', 'Date of appointment']
Types: ['text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Omonia', 'Giorgos Savvidis', 'Resigned', '4 March 2008', 'Nedim Tutić', '4 March 2008']
SQL:

assistant: SELECT "Outgoing manager" FROM "Table" WHERE "Replaced by" = 'Thomas von Heesen';