The Buccaneers crashed out of the continental tournament in group stages after losing to Guinean champions Horoya AC last month.
Mosimane, who guided the Brazilians to the Champions League knockout stages, also stated that Bucs did well on their return to the competition after a five-year absence.
“Pirates did very well to go to the group stages of the Champions League after not competing in the competition for some time, they did exceptionally well," Mosimane told The Citizen.
"The players don’t have the experience,” the 2016 Champions League winning coach continued.
Mosimane explained that the Buccaneers relied on accomplished players such as Happy Jele, Wayne Sandilands and Asavela Mbekile for experience.
“I think Happy Jele and Wayne Sandilands [and Asavela Mbekile] are the only guys who have the experience," he added.
"But Alfred Ndengane and Thembikosi Lorch have not played in the Champions League and you could see that they lacked experience," Mosimane explained.
The Kagiso-born tactician went on to state that he believes that Bucs will do well in next Champions League campaign as they have a good technical team.
"But it comes with time, they have quality coaches and they will come out of the group stages, it is a question of time," he concluded.
Pirates are currently competing with Sundowns for this season's PSL title with the two South African football giants having played to a 0-0 draw at the Orlando Stadium on Monday.
The top two teams from the PSL will qualify for next season's Champions League.