ใครคือนักแข่งรุ่นเยาว์เมื่อ Alessandro Petacchi ชนะ?ไม่จำเป็นต้องใช้โต๊ะทั้งหมด
Who was the young rider classification when Alessandro Petacchi won?It is not neccessary to use all the tables.
 table_28538368_2:  (young_rider_classification [ VARCHAR ] winner [ VARCHAR) ]
SELECT young_rider_classification FROM table_28538368_2 WHERE winner = "Alessandro Petacchi"