Dereck Lively II still couldn’t believe that the Dallas Mavericks ended up with the first overall pick of this summer’s NBA Draft, which eventually turned out to be Cooper Flagg.

The new contract starts with the 2026-27 season and allows him to opt out of the final year in the summer of 2028, when he'll have 10 years of NBA experience.

During his time suiting up for the Celtics, Nelson wore only jersey No. 28 and put up 4.8 points, 2.8 rebounds, 5.5 assists, ...