Dempo FC striker Junior fell unconscious after being hit in the face by Subrata Paul while scoring his second goal in the 2-0 victory over Calcutta's Mohun Bagan in the Federation Cup final on December 5.
The post mortem report said Junior had suffered a cardiac arrest.
"Subrata Paul admitted his mistake, but said he had no intention of hurting Junior and we accepted his submission," said All India Football Federation (AIFF) disciplinary committee chairman Hardev Jadeja.
"We decided to treat him leniently as he is a young player. We felt he only needs a cooling period."
Paul, 20, was not booked at the time but was later suspended by the AIFF pending Monday's disciplinary hearing. His ban runs until the end of February.
The match referee was also suspended for not booking Paul and for not promptly calling for the ambulance.
The incident led to a national uproar with Dempo officials and the media criticising Paul and blaming the organisers for the delay in taking Junior to hospital.