Cleveland Cavaliers star LeBron James has praised his teammate Kevin Love for the impact that he is having on their first-round playoff series against the Boston Celtics.

Love had been criticised during the regular season, while his relationship with James was reportedly strained as they admitted to the media that they were not best friends.

However, the two-time NBA champion has been left impressed with his performances in the first playoff series of his career.

"He's played an unbelievable series," ESPN quotes James as saying.

"He's been highly criticised this year, and I don't know why.

"I know why. I know why. I know."

Love is averaging 18.3 points and 9.0 rebounds through the Cavs' opening three games of the post-season as they lead Boston 3-0.