Graves said Kramer informed him in a letter Thursday. The letter, a copy of which was obtained by OTL, said Graves had been repeatedly late for practice.
Earlier this month, Graves said Kramer had pushed him to the ground during an Oct. 3 practice. After the school conducted an investigation, Kramer was suspended for Saturday's football game against Montana.
The Pocatello (Idaho) City Attorney's Office is also considering misdemeanor charges against Kramer. As of Thursday, city attorney Dean Tranmer said no final decision had been made.
Kramer's letter said Graves had been warned about being late and referred to two specific practices -- those on Wednesday and Thursday.
"I was never warned," said Graves, who hasn't practiced or played since the incident Oct. 3, at which time he said he suffered a neck injury. "I was also never informed of what time I had to be at practice since I have been out.
"(Wednesday), I got there five minutes after practice started. (Thursday), I wasn't late at all. I'm assuming this is a personal vendetta by Coach Kramer. He's acting differently toward me since the incident."
Graves' attorney, Donald Jackson, said he considers the suspension to be retaliation for Graves' refusal to drop the criminal case against Kramer.
Jackson also said Graves has not been medically cleared to play.
Idaho State assistant athletic director for media relations Steve Schaack said Graves has been suspended "for a violation of team rules."
Schaack said the school had no further comment.