Nachbar helped lead the Slovenian national basketball team to a fourth place at EuroBasket 2009.

Nachbar started his professional career by joining the Olimpija Ljubljana basketball club in the 1997–98 season.

In the 2000–01 season he signed with Benetton Treviso basketball club, as the youngest Italian League player.

He had a great season with New Jersey as the team's 6th man, making many contributions to the club before they lost in the Eastern Conference semis to the Cleveland Cavaliers.

Nachbar's final NBA game was played on April 16, 2008, in a 94–105 loss to the Boston Celtics where he recorded 11 points, 1 assist and 1 block.

In July 2009, he signed a 2-year contract with a team option for the second year with the Turkish League club Efes Pilsen.

[8][9] After not getting a contract in the NBA, Nachbar signed with Russian League team UNICS Kazan in January 2012, until the end of the season.

He also helped the team regain their Basketball Bundesliga title, as they won 3–0 in the finals series against EWE Baskets Oldenburg.

[18] His younger brother Grega is assistant coach of Premier A Slovenian Basketball League club Helios Suns.