According to the Football411.com website, Daine Klate scored the only goal of the match after 53 minutes in a game that was there for the taking for both sides.
While Bucs struggled to play their usual brand of attacking football, Stars pushed them all the way, hitting the upright of the goals on two occasions.
After the match De Sa said: "It wasn't the best game of football, but that's three points for us and that's all that matters. It was important to beat a team that's been doing very well and move away from them a bit.
"It's that stage of the season now when we have to grind out results. They came for a draw I thought, but we got the goal and a good three points.
"They were a bit cagey and sat back and waited for us to play before going on the counter. Daine (Klate) had an early chance which he should have put away, but then we got the goal and they moved up a bit more, but were still cagey."
The result saw Pirates keep pace with Kaizer Chiefs, who beat Black leopards 3-1, at the top of the table, in second place just two points behind their arch-rivals and with a game in hand. Dikwena are in third, a further three points adrift of Bucs.