user: Question: What is the Grid for Rider Ruben Xaus?
Columns: ['Rider', 'Bike', 'Laps', 'Time', 'Grid']
Types: ['text', 'text', 'real', 'text', 'real']
Sample row: ['Max Biaggi', 'Suzuki GSX-R1000 K7', 24.0, '39:24.967', 4.0]
SQL:

assistant: SELECT "Grid" FROM "Table" WHERE "Rider" = 'Ruben Xaus';