Pat Riley and Danny Ainge faced each other as part of the Lakers-Celtics rivalry. They were on either side of one of the NBA's biggest ever brawls. They coached against each other. None of that amounted to beef.

But decades into their parallel careers, Riley and Ainge became rival executives -- for the Celtics and Miami Heat, respectively -- and once provoked, their mutual animus suddenly saw the light of day. Executive beef is a whole other flavor, the stuff of press releases and seemingly pointed transactions.

This beef took a while to marinate, but for the brief period it flared up, it was pretty funny.