ESPN has put together a list of the Top 10 Biggest Athletes of the 20th Century. Check out the list below.
1

Michael Jeffrey Jordan is a retired American professional basketball player
***
2

George Herman Ruth, Jr , also known as 'Babe', 'The Great Bambino', 'The Sultan of Swat', 'The King of Crash', 'The Titan of Terror' and 'The Colossus of Clout', was an American Major League baseball player from 1914-1935.
***
3

Muhammad Ali is a retired American boxer and former three-time World Heavyweight Champion and winner of an Olympic Light-heavyweight gold medal
***
4

James Nathaniel Brown is an American former professional football player who has also made his mark as an actor and social activist
***
5

Wayne Douglas Gretzky, OC is a retired Canadian professional ice hockey player who is currently part-owner and sport head coach of the Phoenix Coyotes.
***
6

James Cleveland 'Jesse' Owens was an American track and field track and field athlete.
***
7

Jacobus Franciscus "Jim" Thorpe was an American athlete
***
8

Willie Howard Mays, Jr is a retired American baseball player who played the majority of his career with the New York and San Francisco Giants and before finishing his career with the New York Mets.
***
9

Jack William Nicklaus, also known as "The Golden Bear", is widely regarded as the greatest professional golfer of all time, in large part because of his records in major championships
***
10

Mildred Ella "Babe" Didrikson Zaharias was an American athlete considered to be perhaps the greatest all-around female athlete of all time
***