The Celtics acquired Luis Jr. for Niang, who will likely spend his rookie season in Maine. Luis Jr. went undrafted out of St. John's, where he played two seasons after he started his college career at UMass. The 6-foot-7 guard averaged 14.1 points off 43.9 percent shooting and 5.6 rebounds per game over his three collegiate seasons.

By moving the final year of Niang's contract ($8.2 million), the Celtics are now firmly under the second salary-cap apron.

The Celtics made a pair of moves Tuesday to slightly alter their roster while also saving some money in the process.