[1] In a 2009 Yahoo Sports article, Nelson was ranked the third-best general manager of the decade after producing nine 50-plus-win seasons in a row and the first finals appearance in franchise history in 2006.

Wishing to remain closer to his mother, Donnie gave up on playing in Iowa or Indiana, and instead went to the Division III Wheaton College in Illinois, where his older sister Julie studied.

[5] Nelson's first works with the NBA were in his father's teams, first as a regional scout of the Milwaukee Bucks between 1984 and 1986, and then as the top assistant to Don in the Golden State Warriors from 1986 to 1994.

[5] After the 1988 Summer Olympics, Marciulionis invited Nelson to Lithuania, where for three months he lived in the player's apartment in Vilnius, staging a series of basketball clinics around the increasingly restive republic.

[6][11] During the 2001–02 NBA season, Nelson was interim head coach of the Mavericks while his father recovered from cancer treatment, leading the team to a 15–8 record.

[citation needed] Nelson acquired the core group of players on the 2011 championship Mavs roster through key trades and success in the NBA draft.

On previous teams, Nelson played a role in trading for players such as two-time MVP Steve Nash and All-Star/Sixth Man of the Year Antawn Jamison, as well as acquiring future All-Stars Devin Harris and Josh Howard via the draft.

[citation needed] Key pieces of the modern Mavericks roster were once again assembled through impressive trades and Draft night success orchestrated by Nelson.

Nelson has earned a reputation in basketball as arguably the greatest international scout of all-time considering his groundbreaking involvement in Eastern Europe (Marčiulionis) and China (Wang) combined with his role in acquiring future MVPs Steve Nash (Canada) and Dirk Nowitzki (Germany), All-Star Kristaps Porziņģis (Latvia), and Rookie of the Year Luka Dončić (Slovenia).

He also famously advocated for the Mavericks to draft future MVP Giannis Antetokounmpo (Greece) in 2013, only to be rebuffed by owner Mark Cuban.

[13] As the Mavericks established an NBA G League (D-League) team in Frisco, Texas, a suburb north of Dallas, Nelson was named co-owner.

Knowing of Marčiulionis's struggles, Nelson helped get sponsors for the Lithuanian team's 1992 Summer Olympics campaign, which included rock band Grateful Dead.

He is the founder of the "Global Games" in Dallas, which gives area high school kids a chance to test themselves against the top Junior National teams in the world.