user: Question: What was the tie number for the round against visiting opponent Chelsea?
Columns: ['Tie no', 'Home team', 'Score', 'Away team', 'Date']
Types: ['real', 'text', 'text', 'text', 'text']
Sample row: [1.0, 'Blackpool', '6–2', 'Fulham', '26 January 1957']
SQL:

assistant: SELECT "Tie no" FROM "Table" WHERE "Away team" = 'Chelsea';