According to a Phoenix Police Department incident report, obtained by TMZ Sports, Eubanks made the complaint roughly five hours after he and Stewart were involved in an altercation at the Footprint Center just prior to the Pistons vs. Suns Feb. 14 matchup.

Eubanks, cops wrote in the report, said Stewart confronted him while he was entering the arena due to interactions the two had previously had while playing in a game three months prior.

"He got off the bus and he started, um, just talking s***," Eubanks told cops. "He said something along the lines of, 'You wanna run it back? We're right here. We can do it right now.'"

Cops say Eubanks told them he tried to walk away from the situation, but Stewart kept advancing toward him ... until they were face-to-face inside of a tunnel in the arena.

Eubanks told cops, according to the report, Isaiah then said, "We can do this s*** right now" ... before he threw "a sucker punch."

Eubanks stated the blow landed in the center of his mouth, causing his gums to bleed. He added, the report states, "My teeth definitely are like looser and they hurt."

When pressed more about why he believed Stewart was so upset, Eubanks stated nothing out of the ordinary happened between the two in their previous matchup.

"Just basketball stuff," the Phoenix center said. "It was, you know, lowering your shoulder. Trying to hit, hit somebody for a box out. Being physical. Talking on the court. That's all it was."

At the time, Eubanks told cops he wished to prosecute ... and Stewart was issued a citation.

However, the report states that on Feb. 17 -- three days after the encounter -- Eubanks called cops and said he no longer wished to press charges.

On Feb. 19, cops say Eubanks told them "he had been thinking about the incident for a couple days and at the time, he was upset, but had time to think about it."

Stewart was still suspended by the NBA for three games. After serving the ban, he apologized to his team during a meeting with media members.