Mathias, 26, is 6-foot-4 and appeared in eight games with the 76ers last season for his first action as an NBA player. Philadelphia signed Mathias to a two-way deal before releasing him in January.
He has also spent time with the Texas Legends of the G League and Spanish club Joventut.
As Scotto noted, Mathias also was a member of of Team USA’s AmeriCup qualifying roster ahead of the Tokyo Olympics in July.
The Ignite are based out of Walnut Creek, Calif., and are entering their second season. Former NBA guard Jason Hart will serve as their head coach in 2020-21.