The 26-year-old is believed to have caught the attention of Chiefs coach Steve Komphela.
"Lots of agents have approached Mahlasela informing him Chiefs are looking to sign him," a well-placed source tells KickOff.com.
"His phone rings non-stop with agents begging to represent him. Because the player doesn't have an agent, it seems Chiefs have been dealing directly with Celtic about the player."
The Orlando Pirates development product is contracted to Celtic until June 2018.
Mahlasela made 20 appearances in the league in 2016/17, scoring twice and providing two assists in all competitions.