King, 27, is 6-foot-6 and has been playing for the Agua Caliente Clippers of the G League, averaging 15.5 points, 5.3 rebounds and 2.5 assists.
This becomes the third signing for the Mavericks in just a few days, as they have also added shooting guard Theo Pinson (story) and forward Marquese Chriss (story) on 10-day deals.
King has appeared in one game for his career, in 2018-19 with the Suns. He has also played in Germany, Poland and Italy, as well as with the G League’s Northern Arizona Suns. He was waived by the LA Clippers in training camp.