The incident went down during the first quarter, when the Cav’s forward went to set a screen and inadvertently head-butted Tatum.
Love was removed from the court with less than seven minutes left in the quarter, so he could undergo medical evaluation. At halftime, the team announced he would not return to the game, which the Cavaliers won, 109-99.
On Saturday, Cleveland confirmed Love has been placed in the NBA's concussion protocol, and will miss the decisive Game 7 on Sunday.
Love missed Game 3 in the 2016 Finals due to a concussion, and missed a March 28 matchup this season for the same reason.
Game 7 will go down at 8:30 p.m. on Sunday. If the Cavaliers come out on top, they will head to their fourth consecutive NBA Finals.