Mamukelashvili was ejected after being assessed for a Flagrant 2 after shoving Thomas Bryant from behind in Saturday's game versus the Pacers with 1:35 remaining in the fourth quarter.
Mamukelashvili posted eight points (2-4 FG, 1-3 3Pt, 3-6 FT), six rebounds and one assist over 17 minutes during Friday's 140-113 loss to the Kings.
Mamukelashvili tallied 14 points (4-5 FG, 3-4 3Pt, 3-4 FT), three rebounds, one assist and one steal in 18 minutes during Monday's 112-107 preseason loss to the Thunder.
The Spurs signed Mamukelashvili to a one-year, $2.2 million contract Tuesday, Adrian Wojnarowski of ESPN reports.
San Antonio renounced their free agent rights on Mamukelashvili on Monday, Keith Smith of Spotrac.com reports.
The Spurs extended a qualifying offer to Mamukelashvili on Sunday, Jeff Garcia of KENS 5 San Antonio reports.
Mamukelashvili posted 18 points (7-13 FG, 3-6 3Pt, 1-2 FT), eight rebounds and one assist over 26 minutes during Sunday's 123-95 win over Detroit.
Mamukelashvili totaled 21 points (8-14 FG, 3-5 3Pt, 2-4 FT), 12 rebounds, two assists and one block across 30 minutes during Friday's 121-120 victory over the Nuggets.
Mamukelashvili closed Tuesday's 102-87 win over the Grizzlies with 11 points (4-6 FG, 1-3 3Pt, 2-2 FT), 16 rebounds, four assists and one block in 26 minutes.
Mamukelashvili will join the starting lineup for Tuesday's game against Memphis.