LeBron James vs. Kyrie Irving
This feud started from the moment that LeBron James arrived in Cleveland, but came to a head in the summer of 2017. Immediately after James returned back to Cleveland in 2014, he clashed with Kyrie Irving, as he viewed the latter as being something of a selfish player, who was more about himself and his own statistics, at the expense of making his teammates better. Irving eventually began maturing as a player, but chafed under James’ constant prodding, criticism, and condescension.
Knowing that James could potentially leave Cleveland after the 2017-2018 season, and highly miffed at the idea that Cleveland would consider shopping him in the first place, Irving demanded a trade by the Cavaliers in the summer of 2017, leading to the deal that sent him to the Boston Celtics.