Gcaba and Ngoma were among the six signings Irvin Khoza formally announced this morning, the others being Onyekachi Okonkwo, Patrick Phungwayo, Manti Moholo and Khethokwakhe Masuku.
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Gcaba is a versatile player who can play at central defence and at left-back, while Ngoma plays as an attacking midfielder,both on the left wing and behind the strikers, where he excelled during his stint at University of Pretoria last season.
Ngoma was on the wanted lists of Bidvest Wits and Ajax Cape Town, but he says he wanted to win trophies.
"It feels great – and the excitement is still sinking in," the Tshwane-born midfielder tells KickOff.com.
"Both Ajax and Wits were interested but I decided to join Orlando Pirates because I want to win trophies!"
Gcaba, meanwhile, says he is confident of success at Bucs.
"I am not afraid of competition," he says. "I like facing big challenges because they motivate me to work hard to earn my spot, and wear the back and white jersey."
The KwaZulu-Natal-born defender says he wants to help Pirates continue their success.
"I want to help the club retain the League and fight for the other competitions in the PSL," he says.