Robin Lopez Yells at Ref, Throws Chair After Being Ejected from Bulls vs. Kings

Chicago Bulls big man Robin Lopez was not happy to be ejected from Monday's game against the Sacramento Kings.

Lopez initially grew angry after receiving a technical foul with 4:21 left in the second quarter. He continued arguing with the referee while walking toward the Bulls' bench and promptly received a second technical. At that point, teammates Bobby Portis and Justin Holiday helped escort him off the court:

Robin Lopez Lose His Cool and Gets Ejected

Twitter user Kooper Richardson also showed Lopez throwing a chair in the tunnel on his way to the locker room:

NBC Sports Chicago noted Lopez wasn't the first Bulls center to have an outburst during a game in Sacramento:

Lopez's on-court eruption draws more attention to the ongoing tensions between players and referees.

"The No. 1 issue on [players'] minds is officiating," said NBA Players Association executive director Michele Roberts in January, per USA Today's Sam Amick. "And it's only gotten worse over the years, [and] probably now is about as hot as it has been."

A group of referees and NBA players are planning to meet during All-Star Weekend, which begins Feb. 16 in Los Angeles.

The NBA also announced a "five-pronged initiative designed to address the on-court working relationship between NBA players and referees" last month.

As part of the plan, head of referee operations Michelle Johnson and former referee Monty McCutchen will work with current officials to improve their conflict resolution techniques. The NBA's referee operations department will also speak with players, coaches and team officials to address any misunderstandings regarding how league rules are interpreted and enforced.