Down double digits in the fourth quarter against the Portland Trail Blazers, Hart picked up two consecutive technical fouls for arguing with the official and was forced into the locker room early.
This was the second time in the summer league that Hart was ejected, although the first came in Sacramento.
His last game in Las Vegas ended with just 12 points on 3-of-12 shooting, including 0-of-6 from three-point range. The Lakers eventually suffered a 91-73 loss to the Blazers while failing to defend their title from last season.
Despite the disappointing finish, Hart's skill set was on display throughout the summer.
The 2017 first-round draft pick was named the Las Vegas Summer League MVP after averaging 24.2 points per game in his first seven contests, including a team record 37 points in the semifinals against the Cleveland Cavaliers.
Not only was his scoring average the most of anyone who played at least three games, he was efficient from all over the court and knocked down 39.6 percent of his outside shots.
Averaging 7.9 points per game as a rookie for the Lakers last season, he appears ready to take the next step in his second year.