National Football League (India)
The National Football League (commonly known as the NFL) was an association football league competition in India between 1996 and 2007 which was organised into three divisions. The league is now transformed into the I-League and continues with that name. The "Premier Division" of the league was first introduced in 1996, though the country already had a long history in the sport thanks to the likes of the IFA Shield and the Federation Cup. In fact, the Santosh Trophy (started in 1941) was the top football competition in the country before the then National Football League started.
Indian Super League
Unlike most football leagues around the world, the Indian Super League does not use promotion and relegation, instead choosing to grow the league through expansion, similar to Major League Soccer in the United States. During the league's first four seasons, two teams have been crowned champions, both winning twice each. ATK won the first title in 2014 before winning their second title in 2016. Chennaiyin are the other club to be crowned as champions, having done so in both 2015 and 2018.