The Buccaneers are nowleft with only a mathematical chance of defending their crown. And if leaders Kaizer Chiefs beat Ajax Cape Town on Wednesday night, Pirates would be dumped from the title race.
"We've got to keep on winning all our games. We can't throw in the towel," De Sa said.
"We've got to get maximum points every time we play."
Appointed by the Soweto giants earlier this season, De Sa was unsure if his job was in jeopardy following their midweek loss, which gave Chippa some hope of avoiding relegation in their maiden season.
"If you're asking me about staying or leaving, that's not my decision," De Sa said.
"I'm here to do a job and that's it. We do the best we can with what we have and we'll continue to do so."
Pirates had used a different line-up from their previous league match – a 1-0 win over Wits three days earlier.
"We tried to take the game to them. We put in a couple fresh legs after some of the guys were tired from Saturday night.
"We tried different players, different ways."
Ultimately Pirates wasted their opportunities and it came back to haunt them, according to De Sa, as they conceded a goal with four minutes left.
"We had a couple of half chances – by Khethowakhe Masuku and Collins Mbesuma – but when you don't score you can get caught on a sucker punch.
"That's what happens when you play these teams. They're always going to catch you on the break and we got caught."
De Sa had also warned his charges at the break about the potential threat Chippa posed at set-pieces.
"I told them at half-time, 'no silly free kicks', because they look very dangerous on set plays and that's how the goal came about.
"I just think that the guys tried. A couple of very basic errors, and when you can't take a corner kick and lift the ball more than a metre off the ground, that's disappointing.
"It happens and we have to take it on the chin." – Sapa