The Indian Super League is investigating allegations that former Arsenal star Robert Pires was punched by an opposition coach while playing for FC Goa.

Pires, part of the Gunners' 'Invincibles' squad that went through the entire 2003-04 Premier League campaign unbeaten en route to winning the title, is alleged to have been struck by Atletico de Kolkata coach Antonio Lopez Habas in the tunnel as the teams walked off at half-time in their ISL game on Thursday.

An ISL spokesperson confirmed to Press Association Sport that both teams had submitted a written report and that the All India Football Federation's disciplinary committee was looking into the evidence.

Pires was heavily involved in Goa's 2-1 home defeat. The game, played in the Goan capital Margao, featured seven yellow cards, while Atletico goalkeeping coach Deshi Bakhtaver was also sent to the stands.

On Friday, ISL spokesperson Leeladhar Singh told Press Association Sport: ''Both clubs have submitted written letters. The disciplinary committee at the AIFF is reviewing the incident.

''They will pronounce the verdict as and when the conclusion is made from the evidence. The AIFF disciplinary committee will look at the evidence as well as the letters (submitted by both clubs).

''It would be too early to predict what the outcome will be. The AIFF will look at all the evidence. They are looking into all the aspects (of the alleged incident).''

Following the game Goa's Brazilian coach Zico told the Indian media at a press conference: ''Pires said he was punched in the face by the Atletico coach and it is very shameful.

''I am telling you what my players told me. I didn't see that myself but I don't think that Pires would lie and say something that didn't happen.

''And when the team entered the field in the second half, they were very nervous and during the half-time we were only trying to control their nerves and calm them down.''

Responding to the allegations on Thursday, Atletico co-owner Utsav Parekh told www.telegraphindia.com: ''Look, none of us were present on the spot when the alleged incident took place. So it wouldn't be proper for us to comment on who's right and who's wrong.

''CCTV footage is available and so it will not be very difficult to establish the truth. Whatever the incident, one can find that out from the CCTV footage.

"So we will not be commenting on what Zico has said, we will wait for the ISL to investigate the matter first.''

Atletico de Kolkata, who are co-owned by reigning Spanish league champions Atletico Madrid, are the current leaders in the inaugural ISL season with 10 points from four games, with FC Goa in sixth place.

Kolkata and Goa are traditional powerhouses of Indian club football, with their rivalry evident from the start of the game, which also saw former Arsenal man Andre Santos score for FC Goa in the first half.

Players had been involved in heated exchanges leading up to the half-time whistle, though it is not yet clear what sparked the alleged incident involving Pires and Habas.

FC Goa confirmed on Friday evening they had reported the various incidents from the match and called for strong action from Indian football's governing body.

In a statement released to Press Association Sport, the franchise's media manager Rhys Mascarenhas said: "The team manager of FC Goa Mr Jonathan D'Sousa has complained to the match commissioner that the referee should have expelled Atletico de Kolkata player Fikru Tefera Lemessa for headbutting FC Goa player Gregory Arnolin at the match played between FC Goa and Atletico de Kolkata.

"Mr D'sousa has also complained to the match commissioner regarding the assault by the head coach of Atletico de Kolkata, on FC Goa's marquee player Robert Pires in the area in front of the players' dressing rooms during the half-time interval.

"The team manager of FC Goa has requested that the disciplinary committee take strong disciplinary action against the players and officials of Atletico de Kolkata for their violent conduct."