Nuggets rookie Michael Porter Jr. suffered a left knee sprain during a minicamp scrimmage Wednesday night and is unlikely to play in the Las Vegas Summer League, a league source told The Denver Post.

Porter drove aggressively on the baseline late in the scrimmage, went up, took contact in the air and came down awkwardly, according to a league source. A foul was called on the play and Porter shot free throws before walking to the sideline.

It’s not expected to be a long-term issue, and the Nuggets see no need to rush him back to the court for Summer League play.

“You feel bad, because the kid has been putting in a lot of work, and he was excited to play,” Nuggets Summer League coach Jordi Fernandez told reporters Thursday. “But obviously the most important thing for him is to be ready for the NBA season. Again, it’s nothing major.”

Porter has looked excellent over the last few weeks as the Nuggets have conducted 5-on-5 scrimmages, and buzz had been mounting about his professional debut. That debut will now be delayed. The Nuggets open their Summer League schedule against Phoenix on Friday night.

On Monday, Porter met with reporters and said his goal was to “dominate” the upcoming Summer League.

“I feel good,” Porter said. “I just can’t wait to really test myself in a real game, because I haven’t played in a game in a while.”

It’s an unfortunate setback for Porter, who has waited more than 15 months since his last competitive game. Porter has worn a brace on his left leg and around his ankle at times during minicamp.

It’s unclear what sort of ramifications it could have on the Nuggets and whether they might be more compelled to match an offer sheet for restricted free agent Trey Lyles, who plays the same position.

Porter “redshirted” last season while recovering from back surgery. He is expected to play a significant role this upcoming season.