Dallas Don Nelson, the second-winningest coach in NBA history, resigned as coach of the Dallas Mavericks on Saturday and turned the team over to protege Avery Johnson.
"I see a little slippage as a team," Nelson said. "The team is just responding better to Avery at this point."
The 64-year-old Nelson also had the title of general manager, but most of those duties were done by his son, Donnie, the team's president of basketball operations. The elder Nelson will stay with the team as a consultant.
"Nellie has earned the right to approach this any way he wants," team owner Mark Cuban said. "I just wanted to be supportive of any direction he wants to go."
Nelson leaves with a career record of 1,190-880 over 27 seasons, including stints with Milwaukee, Golden State and the New York Knicks. Only Lenny Wilkens has won more games as a coach -- 1,332. Wilkens stepped down as coach of the New York Knicks earlier this season.
Although he never won a championship, or even made it to the NBA Finals, Nelson was considered a master of mismatches who won games early in his career by stressing defense then later made a mark with clubs that tried outscoring everyone. Nelson went 339-251 in Dallas, tops in franchise history both in wins and winning percentage.