NBA trade grades: What the trade of Josh Richardson to Boston means for the Celtics and Mavericks

New Boston Celtics president of basketball operations Brad Stevens stayed busy Friday, making a second trade the day after the draft to land Josh Richardson following the Dallas Mavericks swingman's decision to pick up his 2021-22 player option.

How does adding Richardson affect the Celtics' willingness to bring back unrestricted free agent Evan Fournier? And why is Kyle Lowry a big winner of the Mavericks moving Richardson's contract?

The deal

Celtics get: Richardson

Mavericks get: Moses Brown