Philadelphia 76ers' All-Star Jimmy Butler apparently has some issues with the way he is being used alongside Joel Embiid and Ben Simmons.

According to a report by ESPN's Adrian Wojnarowski and Ramona Shelburne, Butler has "aggressively challenged" head coach Brett Brown about his role in the Sixers' offense. 

Woj and Shelburne report Butler has "been vocal in his contesting of Brown and his system," which includes a recent film session in Portland that some onlookers described as "disrespectful" and "beyond normal player-coach discourse." 

Per ESPN:

"Butler has expressed a desire to teammates that he hopes to play in more traditional pick-and-roll and isolation sets, rather than trying to find his place in the Sixers free-flowing offense, league sources said. In searching for answers, Butler has met privately with Brown and his coaching staff, as well as general manager Elton Brand, league sources told ESPN."

That said, Brown has reportedly told those within the organization that he had no issues with his exchange with Butler, and considered it within the confines of the relationship that he's developed with the 29-year old star.

The Sixers, 25-14, acquired Butler via trade with Minnesota in mid-November, and they are 14-8 since the deal. The five-time All-Star can become a free agent this Summer, but Philadelphia remains committed to making the Big-3 of Butler, Embiid and Simmons work in the long-term.