#2 Norman Whiteside
Former Northern Ireland and Manchester United attacking player Norman Whiteside is the youngest player in history to make an appearance in a FIFA World Cup. During the 1982 World Cup, in Spain, Whiteside made his debut at the age of 17 years, 1 month, and 10 days in a game between Yugoslavia and Northern Ireland that ended 0-0.
Whiteside was selected as part of the national team set-up for the World Cup, because of some brilliant displays for his club Manchester United as a 17-year-old. Whiteside, however, didn't win many honours during his career.
A move to Everton was confirmed in 1989 as Whiteside spent two more years playing at the highest level with the Blues of Merseyside before calling time on his career. Whiteside played in two World Cups but didn't perform as well as he could have.