He was later joined by Mavericks guard Dennis Smith Jr. and Thunder guard Terrence Ferguson as members of the 2017 draft class to sign with Under Armour .
On June 21 , the day before the 2017 NBA draft , Jackson signed a multi-year endorsement deal with Under Armour .
Jackson was later joined by Mavericks guard Dennis Smith Jr. and Thunder guard Terrence Ferguson as members of the 2017 draft class to sign with Under Armour .
On June 21 , the day before the 2017 NBA draft , Jackson signed a multi-year endorsement deal with Under Armour .