The players which have been included to the initial 27-man squad are goalkeeper Wayne Sandilands, midfielder Luvuyo Memela and defender Thabo Matlaba.
This was confirmed by Pirates' administrative officer Floyd Mbele, who stressed the importance of having enough depth as they compete in the Champions League and PSL.
“After extensive consultation with the technical team, I can confirm that we have registered the three players in question into the Caf Champions League squad," Mbele said on the club's official website.
“As you already know, Caf allows clubs to register a total of 30 players for the competition and as a club, we had decided to register only 27 players at the time as we felt this number was sufficient to get us through the preliminary stages of the competition which we did," he continued.
“Now that we have to juggle between a congested league season and travelling around the continent for the Champions League, it’s important that we have enough players in both competitions to allow the technical team enough depth to compete," he concluded.
Pirates will be looking to return to winning ways when they lock horns with Tunisian giants Esperance in the Champions League Group B match on Saturday.
The Buccaneers were booted out of the 2018/19 Nedbank Cup by Black Leopards in the round of 32 last weekend, meaning they are now vying for the Champions League and PSL crowns this season.
The encounter between Pirates and Esperance will be played at the Orlando Stadium and kick-off is at 21h00.