The win snapped the Tigers' 32-game SEC road losing streak. The previous victory was a 75-71 decision at Arkansas on Jan. 28, 2014.
Freshman forward Jontay Porter added 19 points and seven rebounds before fouling out for the Tigers (11-3, 1-0). Senior forward Jordan Barnett also scored 19 points
Missouri was 14-of-24 from 3-point range. Porter was 5-of-7 from behind the arc, Barnett was 4-of-6 and Robertson was 4-of-8.
Junior forward Chris Silva had 18 points for the Gamecocks (9-5, 0-2).
South Carolina, which is in rebuilding mode after last season's historic Final Four run, shot just 38.6 percent from the field and was 5-of-18 from 3-point range.
The Tigers led by as many as 16 points in the first half while ending the conference road skid that lasted nearly four years.
Barnett scored 14 points and Porter had 11 as Missouri held a 39-27 halftime advantage.
Barnett scored six straight points -- including a four-point play -- as the Tigers took a 17-12 lead with 11:23 remaining.
The Gamecocks pulled within 20-19 when freshman forward Felipe Haase connected on a 3-pointer with 8:48 remaining in the half before Barnett and Porter each hit 3-pointers during a 7-0 burst to get the lead up to eight.
Porter made two free throws later in the half to cap a 9-0 run to push Missouri's lead to 36-21 and the margin reached 16 on a 3-pointer by Robertson with 1:17 left.
A 3-pointer by Barnett pushed the Tigers' lead to 57-38 with 12:03 to play. South Carolina was within 16 midway through the half but Porter's 3-pointer with 8:56 left increased the margin to 21.
The Gamecocks used an 8-0 run to cut Missouri's lead to 72-61 with 3:14 to play before the Tigers stymied the surge and finished off the rare conference road victory.
--Field Level Media
Missouri | South Carolina | |
Kassius Robertson 23 | Scoring | Chris Silva 18 |
Jordan Geist 6 | Assists | Maik Kotsar 2 |
Jontay Porter 7 | Rebounds | Frank Booker 5 |
Kassius Robertson 7 | Free Throws Made | Chris Silva 9 |
Jordan Barnett 2 | Steals | Frank Booker 2 |
Jontay Porter 4 | Blocks | Maik Kotsar 3 |
Team | Points | FG% | 3PM-3PA | FTM-FTA | Assists | Rebounds | Blocks | Steals | Turnovers |
Missouri | 79 | 46.9 | 14-24 | 19-24 | 15 | 26 | 8 | 7 | 13 |
South Carolina | 68 | 38.6 | 5-18 | 19-26 | 8 | 27 | 8 | 4 | 11 |