Lauri Markkanen, who left the Chicago Bulls' Tuesday loss at Toronto after experiencing what the team called "extreme fatigue," will sit out the remainder of the season.
The seven-foot forward remained in Toronto overnight Tuesday for testing regarding an accelerated heart rate and fatigue. He returned to Chicago on Wednesday but didn't play in the team's 118-98 home loss to the Portland Trail Blazers on Wednesday night.
The Bulls announced after the Wednesday game that all testing on Markannen had been normal, but he will continue to be assessed for 10-14 days. Chicago have six games left, with the season ending on April 10.
"The long-term health of our players is always our organisation's top priority," Bulls executive vice-president of basketball operations John Paxson said in a statement. "We will continue to monitor Lauri's condition and work with our medical staff and doctors to provide him with everything he may need."
In 52 games this season (51 starts), Markannen averaged 18.7 points, nine rebounds and 1.4 assists.
The Bulls replaced Markannen on the roster by calling up his former University of Arizona teammate, Rawle Alkins, from the Windy City Bulls of the G League.
Alkins scored two points in 16 minutes while appearing in his fourth career NBA game, all this season. He had brief cameos in two games in December and one in February.
"I'm happy to be here, but it's definitely disappointing to miss the (G League) playoffs," Alkins said, according to the Chicago Tribune. "I spoke to the players before I left. I told them to still get this one."