user: Question: Which week was the game against the San Diego Chargers?
Columns: ['Week', 'Date', 'Opponent', 'Result', 'Kickoff [a ]', 'Game site', 'Attendance', 'Record']
Types: ['text', 'text', 'text', 'text', 'text', 'text', 'text', 'text']
Sample row: ['Week', 'Date', 'Opponent', 'Result', 'Kickoff [a ]', 'Game site', 'Attendance', 'Record']
SQL:

assistant: SELECT "Week" FROM "Table" WHERE "Opponent" = 'San Diego Chargers';