The 23-year-old former AS Real Bamako and Djoliba AC player was reportedly spotted during the club's medical assessments.
Pirates recently announced seven new signings, including Yanela Mbuthuma (from Richards Bay), Masindi Nemtajela (Marumo Gallants), Tshepang Moremi (Amazulu), Nkosikhona Ndaba (Richards Bay), Sinoxolo Kwayiba (Chippa United), Tshepo Mashiloane (Baroka), and Sihle Nduli (Stellenbosch).
According to iDiski Times: “He (Mariko) arrived in Johannesburg on Thursday after agreeing a two-year deal with an option to extend.”
The publication reports that the young defensive midfield man was a target for a number of North African clubs.
"He underwent routine medical examination with the club, who have included him in a video on their social channels despite Mariko yet to be announced," they concluded.