user: Question: Which tier is for Football at Tianhe Stadium?
Columns: ['Sport', 'League', 'Tier', 'Club', 'Stadium']
Types: ['text', 'text', 'text', 'text', 'text']
Sample row: ['Football', 'Chinese Super League', '1st', 'Guangzhou Evergrande', 'Tianhe Stadium']
SQL:

assistant: SELECT "Tier" FROM "Table" WHERE "Sport" = 'Football' AND "Stadium" = 'Tianhe Stadium';