Rivers took over the Celtics in 2004 in the midst of the longest title drought in franchise history and — with thanks to the New Big Three of Garnett, Pierce and Ray Allen — guided them to the 2008 NBA title. They returned to the NBA Finals two years later, losing to the Los Angeles Lakers in seven games.
But the Celtics have regressed steadily since then, twice failing to get past the Miami Heat in the Eastern Conference playoffs. This year they finished third in the Atlantic Division — they had won it five straight times — and lost to the New York Knicks in the first round.
That convinced many that it was time to rebuild — a process Rivers was reluctant to supervise. If the Celtics unload Garnett and Pierce, that would leave them with point guard Rajon Rondo as their only established star.
Rivers had the second-longest tenure of any NBA coach to San Antonio’s Gregg Popovich, compiling a 416-305 record in Boston that was the third-most wins in franchise history behind Red Auerbach (795) and Tommy Heinsohn (427). Trades for coaches have occurred about a half-dozen times in NBA history, most recently in 2007 when the Heat received compensation for allowing Stan Van Gundy to go to the Orlando Magic.
In 1983, the Chicago Bulls sent a second-round draft pick to Atlanta as compensation for coach Kevin Loughery. The Hawks used that pick to take Glenn “Doc” Rivers.