Bucs dominated proceedings but found AmaZayoni’s defence a tough nut to crack, and a late penalty from Isaac Chansa separated the teams.
Benedict Vilakazi was sent off for a second bookable offence for protesting against the spot-kick.
Aces probably deserved a share of the spoils, but in the end they were unable to hold Pirates off.
From the first whistle it was clear that Aces’ plan was to flood the midfield in order to frustrate Pirates.
The hosts played with just one genuine striker, Phikolethu Spelman, and three centre backs, while the remainder of their outfield players looked to clog up the middle of the park.
AmaZayoni’s plan worked well for the first 20 minutes, but Bucs gradually began to find some space in wide positions and started to put the home side’s defence under pressure.
On 23 minutes a good cutback from Happy Jele handed Chansa a shooting chance just inside the box but he ballooned his effort high and wide.
Jele himself had a chance 10 minutes later when he latched onto a loose ball in the Aces penalty area, but Fabian McCarthy made a good block to stop the right-back’s goal-bound attempt.
On 40 minutes Francis Chansa was called upon to make a fine save, tipping Thulasizwe Mbuyane’s flick-on over his crossbar.
Aces made a change at the break, with Manqoba Ngwenya replacing Spelman, but 'Shakes' lasted just a few minutes before his right ankle gave way in an awkward fall from an aerial challenge. He tried to run off the injury but was soon replaced my Mpho Maleka.
Just before the hour mark Jele almost scored with a glancing header from a corner-kick – the defender’s effort had the beating of Chansa but David Mathebula cleared the ball off the line.
Bucs continued to dominate proceedings but they were repeatedly frustrated by good defending.
Bucs were inches away from breaking the deadlock in the 83rd minute when Chansa rattled the crossbar from a free-kick.
A minute later Pirates finally got the break their dominance deserved.
McCarthy clumsily tripped up substitute Bongane Ndulula and referee Jerome Damon pointed to the penalty spot.
Vilakazi vociferously protested the decision – and earned his marching orders for a second bookable offence – but replays suggested Damon was correct in awarding the spot-kick.
Chansa took on the responsibility of the penalty and beat his namesake in Aces’ goal to secure a vital win for the Buccaneers.