Porter hasn't played and has largely been away from the team this season for what has been termed personal reasons. He was working his way back and attended his first game Friday night when the Cavs beat the New York Knicks.
That night, however, he had a screaming match with team officials after his locker was moved to an auxiliary area to accommodate new teammate Taurean Prince, who arrived from the Brooklyn Nets with Jarrett Allen in a trade last week. After the episode, Porter was told to clean out his locker and other members of the roster were informed he'd no longer be on the team, sources said.
The Athletic first reported the incident with Porter.
The team picked up an option in Porter's contract last month; he has one year at $1.7 million left on his deal.
The Cavs have been protective when discussing Porter during the season. There had been a plan to hopefully reintegrate him to the roster, though he spent weeks away from his teammates, sources said. His returning to the sideline indicated a progression in that plan, as coach J.B. Bickerstaff told reporters Friday.
"Obviously seeing what we're doing, experiencing the games and those types of things will help him as he returns," Bickerstaff said. "We have a plan in place with KP. He's always been a part of the team, but we wanted him with the guys."
On Monday, Bickerstaff said the organization had done its best to help Porter.
"We all want to see Kevin be successful and I still feel that way, so whatever it is that happens in the future for him, I hope nothing but the best for him," Bickerstaff said. "It's part of our responsibility as coaches to give everyone our all and try to make the best of every situation and I can say that we did that."
Porter, 20, was arrested on Nov. 15 after a middle-of-the-night crash when he flipped his Mercedes SUV. He admitted to have been drinking earlier in the evening, and when police searched the car, they found a loaded handgun in the glove compartment and a small amount of marijuana.
A grand jury declined to indict Porter on a felony weapons charge after he was able to prove he didn't know the gun was in the car. Police also determined he was not impaired at the time of the accident. A judge dismissed the misdemeanor pot charge.
In October, Porter raised alarms when he posted a black square on his Instagram with the message "Do you ever wish to see the end of your time?" After Cavs officials and teammates reached out, Porter deleted his Instagram account.
He later posted a message on Twitter that read in part, "I'm fine. Been thru my worse times already, can't get worse than what I already been thru. Love & Thank you." That post was also later deleted.
The Cavs traded up to take Porter with the No. 30 pick in the 2019 draft. Though he had been regarded as one of the most talented players in the draft, Porter slid after a rocky freshman year at USC when he was suspended at one point for conduct issues.
He had a promising rookie season for the Cavs in 2019-20, averaging 10.0 points, 3.2 rebounds and 2.2 assists in 50 games.