Portland Trail Blazers star CJ McCollum received a PRP injection during the offseason to relieve pain and alleviate minor swelling in his right knee, league sources told Yahoo Sports.

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McCollum, 27, has returned to playing at a high level after receiving the treatment about four months ago, scoring nine points in 12 minutes in Portland’s preseason opener against the Toronto Raptors on Saturday.

McCollum experienced persistent soreness during the latter part of the 2017-18 campaign and sought a remedy at the conclusion of the season, sources said. The Blazers’ season ended April 21 after a first-round playoff sweep by the New Orleans Pelicans.

An MRI revealed no structural damage and he was administered a PRP treatment early in the offseason in Los Angeles, sources said.

The NBA’s 2015-16 Most Improved Player was sidelined from basketball-related activities for nine weeks, sources said.

In his sixth year out of Lehigh University, the 6-foot-3 guard is coming off a season in which he averaged 21.4 points, four rebounds and 3.4 assists.

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