user: Question: Who was the young rider classification when Alessandro Petacchi won?
Columns: ['Stage', 'Winner', 'General classification', 'Points classification', 'Mountains classification', 'Young rider classification']
Types: ['real', 'text', 'text', 'text', 'text', 'text']
Sample row: [1.0, 'HTC-Highroad', 'Marco Pinotti', 'not awarded', 'not awarded', 'Bjørn Selander']
SQL:

assistant: SELECT "Young rider classification" FROM "Table" WHERE "Winner" = 'Alessandro Petacchi';