The teams are also swapping second-round picks in 2022 as part of the deal, league sources said.
Nelson signed with the Pelicans as a free agent on Oct. 22, averaging 5.1 points, 3.6 assists and 2.2 rebounds in 43 games as a reserve. Nelson averaged 11.4 points, 5.1 assists and three rebounds with the Orlando Magic, Dallas Mavericks, Boston Celtics, Denver Nuggets and Pelicans.
Nelson has a history with Pistons president and coach Stan Van Gundy, who coached Nelson with the Magic from 2007-12.
Reed, in his third NBA season, joined the Pistons as part of the Griffin deal. The 27-year-old has career averages of 4.9 points and 3.8 rebounds.
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