Obviously this depends on where and who we are dealing with. I'm going to look at Baseball players in the USA and soccer players in England in the 1920s.

During this period soccer in England was subject to a maximum wage limit set by the league. Matthew Taylor has calculated this as £386 pa in1924. This compares to £182 for a skilled worker so footballers were paid substantially more than the top of their peer group but still within the region expected for working class men. £1 in this period was worth about $4.90. Players could also get a benefit match after five years.

Baseball players were paid a wider variety of salaries. Babe Ruth was the exception getting $70,000 in1927 on a Yankees team where other star players got between $8,000 to $17,000. This put them well ahead of workers but nowhere near the elite position of today. Ruth's salary still amounts to only about $750,000 in1996 dollars.

It is also important to question what category we should put sportsmen into. They come from working class backgrounds and the discourse of sports keeps them in a subordinate relationship to their employers; game cheques, autocratic coaches and all powerful commissioners. Players are addressed as "boys" or "lads". However they are highly sought after specialists in a valuable industry. By that scale they were not unusually well paid.

Sources:

Matthew Taylor, 'Beyond the maximum wage: the earnings of football professionals in England 1900-1939' in Soccer and Society vol. 2, no. 3, Autumn 2001.

Paul Stadohaur, Baseball's changing salary structure at http://www.bls.gov/opub/mlr/cwc/baseballs-changing-salary-structure.pdf