
In October 2017, several players complained that Stephen Constantine wasn’t tactically equipped to coach the Indian national team. One of those players was the all-time top goalscorer for India, Sunil Chhetri.
Many, including football analysts and experts believe that there was an ongoing tiff between the coach and the captain of the Indian national football team, due to which Sandesh Jhingan captained the Indian side against China.
#1 Zlatan Ibrahimovic and Pep Guardiola

That is where the good relationship ended between them, as Lionel Messi had the best season of his life playing at centre forward, forcing the Swede to play out wide. Zlatan was still successful, scoring 22 goals in his first 46 matches at the Catalan club.
Ibrahimovic also called the Catalan, a ‘spineless coward’ in his autobiography, and since then has admitted that he is a great manager, but not a good man.
Since then, Ibrahimovic has had successful spells at AC Milan, PSG, and Manchester United.
#2 Nicolas Anelka and Raymond Domenech

French fans were expecting a good comeback from their team in the 2010 World Cup, but their star forward Nicolas Anelka had a fallout with the manager. He slated the manager publicly after a defeat to Mexico, and apparently insulted the manager in the dressing room at half time as well. He was immediately sent home after the Mexico defeat.
France ended up finishing fourth in a group which had the likes of Mexico and hosts South Africa.
#3 Roy Keane and Mick McCarthy

Keane wasn’t happy with Ireland’s preparations and training methods ahead of the 2002 World Cup, and had his feelings known to the manager. Both had an exchange of words, in which both men involved verbally abused each other. Subsequently Roy Keane was stripped of the captaincy, and sent home immediately from their camp in Asia.
#4 Iker Casillas and Jose Mourinho

One was a hero who had won two Champions League titles at the club in the past 15 years, and the other had just won the league with a record points total, and was the best manager in the world at the moment.
Mourinho dropped Casillas for Diego Lopez for the rest of the season before leaving for Chelsea at the end of the season. The following season, Casillas won his third Champions League trophy with Real Madrid before moving on to Porto.
#5 David Beckham and Sir Alex Ferguson

There was big tension at the end of the 2002-03 season between the star man and the manager. Beckham’s fame didn’t help him in solving this feud.
Post defeat to Arsenal in a match, the then Manchester United manager kicked a boot at the superstar, it hit him on the face. This acted as a catalyst for his move to Real Madrid in 2003.