Matsatsantsa nearly opened the scoring around the half-hour mark, but Dove Wome's shot was brilliantly pushed over the crossbar by goalkeeper Daouda Diakite.
At the other end, in-form Stars striker Andrea Fileccia directed a header against the upright just before the recess.
Diakite did well after the break, repeatedly denying Jeremy Brockie in the latter stages of the contest.
Both sides remain in the bottom half of the standings, with Stars in 10th spot with 11 points from eight games, while United are 12th with nine points in as many matches.
The home team produced the first shot on goal in the second minute, but Stars’ Danny Venter fired over from just outside the box.
In the eighth minute Free State had another shot on goal, but Mrisho Ngasa also saw his 22-yard attempt go over the goal.
SuperSport had their first attempt on goal in the 10th minute when Brockie met a corner-kick at the back post, but saw his 14-yard volley superbly saved by Diakite.
The Free State keeper was at his best again when he kept out a powerful 16-yard shot from Wome.
Fileccia nearly broke the deadlock five minutes before the break when he met a right-wing cross from Ngasa, but his ten-yard header struck the post.
Three minutes into the second half Brockie had a great chance to score when he met a low right-wing cross from Fagrie Lakay, but he fired wide from 14-yards out with an empty goal at his mercy.
Ronwen Williams produced a great save in the 62nd minute when an acrobatic dive from the SuperSport keeper saw him tip a 30-yard free-kick from Venter over the crossbar.
A minute later Wome played Brockie in behind the Free State defence, but the striker was denied in a one-on-one situation by Diakite.
In the 69th minute Moeketsi Sekola showed great skill to drive his way into the SuperSport box, but dragged his 14-yard shot wide with just the keeper to beat.
The last twenty minutes saw both teams tighten up their defence which resulted in very few decent chances on goal.