user: Question: When did the Chargers play the Denver Broncos before Week 10?
Columns: ['Week', 'Date', 'Opponent', 'Result', 'Attendance']
Types: ['real', 'text', 'text', 'text', 'real']
Sample row: [1.0, 'September 18, 1977', 'at Oakland Raiders', 'L 24-0', 51022.0]
SQL:

assistant: SELECT "Date" FROM "Table" WHERE "Week" < 10.0 AND "Opponent" = 'Denver Broncos';