The Indian Super League (ISL) has had its fair share of criticism, but its evolution ahead of its fourth season, which starts on Friday, couldn't have been more startling. 

The league has got the biggest criticism off its back by gaining recognition from the Asian Football Confederation (AFC). Its champions will get a spot in the AFC Cup (the equivalent of Europe's Europa League). This means that it's now a proper league, which has to abide by AFC and Fifa statutes.

Two more teams have been added this season —the brand new Jamshedpur FC, backed by the Tata group, and the hugely popular Bengaluru FC, making the switch from the I-League. The ISL will now be a four-month affair—double the length of earlier editions. 

But while this season may be the ISL's most elaborate so far, it will also present it with its biggest test.

The league has done away with the requirement of mandatory signing of a marquee player, and even though Kerala Blasters and ATK have signed strikers Dimitar Berbatov (ex-Manchester United) and Robbie Keane (ex-Tottenham Hotspur), respectively, the other teams will depend on a patchwork of experienced foreigners and turn their focus to strengthening their Indian rosters. This goes hand in hand with the ISL's latest rule—teams need to have at least six Indians on the pitch at all times.

ATK manager Teddy Sheringham, who has won three Premier League titles and scored the equalizer in Manchester United's epic 2-1 Champions League victory over Bayern Munich in 1999, believes this quota system will give more responsibility and playing time to Indians—and develop Indian football in the process.

Three of the 10 head coaches come from England, the home of the Premier League, which has often been criticized for having too many foreigners in starting elevens; in 2005, for instance, Arsenal fielded a team without a single player from the UK. The ISL, however, is slowly moving away from riding on the shoulders of foreign signings to making teams choose from the talent pool within the country.

“It is really important for Indian players to play more. They will get the added responsibility playing live on television week in, week out. You will see some youngsters play for us, not for just 10 minutes in the end, but become a core part of the team," says Chennaiyin FC coach John Gregory. 

Gregory adds that Chennaiyin, which did not sign a marquee player, have diverted their finances towards signing good youngsters. In August, the club signed six Aiff (All India Football Federation) Elite Academy players and many will be seen in action during the ISL.

The other stark difference is in the coaches that the teams have signed. Earlier, players with storied careers would come in as coaches. Some, like Marco Materazzi, were successes while Brazilian great Zico had mixed reviews from his time at FC Goa—just like Roberto Carlos at Delhi Dynamos. This time, teams have gone for coaches who have low playing profiles but have coached extensively around the world and can be described as hands-on trainers. Sheringham is the biggest name, but last year's losing finalists Kerala Blasters went for René Meulensteen. 

The Dutchman was part of Alex Ferguson’s Manchester United coaching set-up for 12 years and was at the forefront of getting the best out of players like Wayne Rooney and Cristiano Ronaldo.

FC Goa have brought in Sergio Lobera, who coached Barcelona's youth teams for close to a decade. NorthEast United FC's João Carlos, who prefers a pragmatic approach on the pitch, immersed himself in researching Indian football three months before the ISL was about to start.

"One should know the culture of the country to understand its players. Even the smallest things, which include those off the pitch. I should know that tandoori roti tastes nice with dal. I have seen my club's matches and I have also seen the last eight matches of the Indian team and followed them at the U17 World Cup," he says.

ATK look the strongest again when it comes to squad depth. Kerala Blasters have a fine strike pairing in Berbatov and Iain Hume, a seasoned ISL campaigner who has a title under his belt.

Jamshedpur come in without pressure but Steve Coppell is a man who knows Indian football after his fantastic campaign with the Blasters last season. FC Pune City have Serbian Ranko Popovic, described as a taskmaster by their winger Kean Lewis. Pune have also signed last year's top-scorer Marcelinho.

Bengaluru FC, a beacon of continuity, will again see Albert Roca and Sunil Chhetri combining. The club, which was playing competitive continental football until recently, has the advantage of a settled unit and has also signed India goalkeeper Gurpreet Singh. 

It will be interesting to watch Chennaiyin under John Gregory; they have a fine midfield maestro in Brazilian Raphael Augusto.

FC Goa's Lobera is clear about the tactics he would deploy. “I come from the Barcelona school of football. My team will keep possession and try and get the ball back as soon as we lose it. You will see good quick short passes and a relentless effort to win the ball back."

Mumbai City FC are the only team which have retained their manager. It took Alexandre Guimarães just two months to mould them into a compact unit that hardly leaked any goals last season. This time, he has four months to work his magic.  "With more time, you will see me experiment with more styles of play," the Costa Rican says.

Mumbai may be without Chhetri but they will have Balwant Singh, who has scored three goals in four matches for India's senior side, leading the line.

This leaves us with Delhi Dynamos, who have also hired a Spanish coach in former Real Madrid player Miguel Angel Portugal. Under him, Delhi are expected to play expressive and possession-based football, but won’t shy away from changing methods when required. His side doesn't look supremely good on paper, but their pre-season performances got better with each result. They lost three of their first four games before winning three matches in a row. 

Blasters striker Hume and Jamshedpur head coach Coppell both point to India's spike in Fifa rankings (currently No.105) as a marker of how far football has come in the country. 

Whether the ISL, so far seen as a two-month extravaganza, is partly responsible for this or not is debatable. But in this new avatar—with more Indians, more matches, and a longer season—the league finally has the chance to make a mark on Indian football.

Close