It is fairly well-recognized that the starting point for the academic field in the Economics of Sports is an article on The Baseball Players’ Labour Market by Simon Rottenberg, published in the Journal of Political Economy in 1956.
The article covers a variety of relevant topics in baseball, including player compensation, league structures such as the draft, the reserve clause, the minor league system, waiver rules. For students interested in any of these topics, this is a fantastic place to start. A key result of the paper is that from an efficiency perspective, the league rules restricting player movement don’t generate any value – though they likely do significantly increase the profitability of professional sports teams.
According to Google Scholar, it has been cited over 1,600 times – searching within those citations for specific sports may be a useful way to start looking for academic articles on narrower topics.