India's World Cup qualifiers opponents, Qatar and Oman's leagues have a mandatory slot for an Asian player much like the ACL and the AFC Cup...
In the Indian domestic club football structure, two leagues run parallely - the Indian Super League (ISL) and the I-League. Winners of both the leagues get a place in the continental competitions administered by the Asian Football Confederation (AFC).
The player regulations in both the ISL and the I-League are pretty similar. For the upcoming 2019-20 season, and ISL club can register a minimum of six foreigners and an optional seventh in their squads.