Porter will miss the Las Vegas Summer League with a left knee strain, a source told The Undefeated, but he is expected to be healthy in time for training camp.
Porter, the 14th overall pick in 2018, had been slated to make his Nuggets debut after missing his rookie season following his second back surgery.
The source said the team decided that playing in the summer league was not reason enough to rush the former Missouri forward back into action.
"You feel bad, because the kid has been putting in a lot of work, and he was excited to play," Nuggets assistant coach Jordi Fernandez told reporters. "But obviously the most important thing for him is to be ready for the NBA season. Again, it's nothing major."
Porter did not have any back issues during practice and scrimmages this week.
The Denver Post first reported that Porter would miss the team's summer league play.