With Kaizer Chiefs having lost to Platinum Stars earlier in the day, Bucs were desperate for the win to close the gap at the top of the standings.
The Clever Boys started the game in a very defensive manner and seemed to have frustrated the home side until a moment of brilliance by Matlaba secured the opening goal.
It was a goal against the run of play in the 33rd minute. Matlaba got the ball just over the half way line and he did not wait too long until firing in a thunderous long-range attempt, which sailed high and over Ryan Harrison and into the top corner.
In the 42nd minute Calvin Kadi and Sibusiso Vilakazi combined well, but Pirates were quick enough to stop the potential danger.
It took three minutes into the second half for Bucs keeper Senzo Meyiwa to have his first save of the game from Ofentse Nato, who just could not get enough power behind his effort.
Then in the 55th minute came the moment of controversy as Wits had a penalty appeal turned down. Calvin Kadi beat Siyabonga Sangweni for pace and the Bucs defender seemed to clip the striker in the box, but the referee waved play on.
And it was Pirates who scored the next goal. This time, Matlaba supplied the ball to Segolela, who flicked the ball over the advancing Harrison for another fine goal.