Don won his 1,000th NBA game. Donnie moved from coaching to become the president of basketball operations for the Mavericks in 2002 while his father was still coaching Dallas. Donnie Nelson was an assistant coach for Lithuania in the 1992, 1996 and 2000 Olympics. Nelson calls Dirk Nowitzki his "German son". Nelson coached Nowitzki for his first six NBA seasons in Dallas. "In my second game ever in the NBA -- obviously I wasn't a defensive presence -- he wanted me out there in the game but he didn't have anybody for me to guard," recalled the 7'0" Nowitzki. "So he let me guard [5-foot-3] Muggsy Bogues for a couple possessions. He said, 'Just stand there in the paint and wave at him. He doesn't want to shoot.'" In the summers, while a player and when he became an NBA coach, Nelson would continually work with his Rock Island High School coach Bob Riley at a basketball camp and the two would play golf after. Riley died in 2009. "He always made sure he checked in on my dad," said Bob's son Jack Riley. Nelson had a hand in the Celtics drafting teammate Steve Kuberski. While with the Celtics, Nelson would return home to the Quad Cities and played with Kuberski, then at Bradley University, at the Moline YMCA. Kuberski was from Moline, Illinois, and had played at Moline High School, a Western Big 6 rival of Nelson's alma mater Rock Island High School. "We were just playing one-on-one but he went back to Boston and said they should take a look at this kid when his class comes up," Kuberski said of Nelson's influence. "They drafted me on whim a year early." After his playing career ended, Nelson refereed basketball games in the summer league, thinking that becoming a referee might be his next career. "I never thought about coaching. I always wondered what in the world I'm going to do when I retire. That's why I tried refereeing", Nelson said. "He sucked as a referee, according to what he tells me", said Nelson's former teammate Joel Novak, who played with Nelson at both Rock Island High School and the University of Iowa. Nelson credits Novak for a lot of his rebounds for missing many shots. During the 1986 season, Nelson established The Don Nelson Fund with the help of the Milwaukee Bucks to aid struggling farmers in Wisconsin.