Shams Charania of The Athletic and Stadium reported the injury is just a mild sprain:
"There's no concern long-term or any seriousness to the knee injury," Charania said.
Lillard first suffered the injury in Game 4 of his team's first-round series against the Los Angeles Lakers. He left the NBA campus in Orlando, Florida, for further evaluation and missed Game 5, which ended up being the final game for Portland as the Lakers clinched the 4-1 series victory.
Though it was a disappointing finish to the season for Lillard, his long-term health remains a priority for a player who is owed $228 million over the next five years.
The five-time All-Star is extremely important to the Trail Blazers' success, which he proved throughout his time in the bubble. He was named the Most Outstanding Player of the seeding games after averaging 37.6 points and 9.6 assists per game in eight games, effectively carrying his team to the playoffs.
Over the full season, Lillard averaged 30.0 points and 8.0 assists per game, both career highs for a player who has been in the top six of MVP voting the past two years.
After barely getting the No. 8 seed in the Western Conference this year, the Blazers could have higher expectations going into 2020-21 if Lillard, Jusuf Nurkic and CJ McCollum can all stay healthy.