2000 Topps Miguel Cabrera - The youngest player ever to appear on a regular Topps Baseball Card
Miguel Cabrera was born in April of 1983. In 1999, he was signed by the Florida Marlins and he appeared in the Topps Traded/Update set in 2000. He was at the ripe old age of 17 years old. I realize today that Topps produces baseball cards of USA team members on the under 18 years of age but they have never been included as part of a regular or update set except for as an insert. I could not find a card of a player that appeared in any Topps set that was younger than Cabrera. In 1969, a bat boy appeared on the Topps card on Aurelio Rodriguez but I don't think that counts. I am also excluding the boyhood photos subset used in the 1972 Topps set (while the photos of the players were from their childhood, the ages of the players in 1972 were more than 17 years old).