Subject to a visa, the 27-year-old second-rower, who is equally as adept in the back-row, will leave United Rugby Championship rivals Vodacom Bulls and join fellow South African JP du Preez and Tongan international Sione Vailanu in Scotland next season.
Born in east London and standing 6’6” Manjezi inspired the Pretoria-based Bulls to the Currie Cup in 2020-21 and said he couldn't turn down a team back in Britain.
“I’m looking forward to the challenge. The opportunity of experiencing a new club outside of South Africa was one I couldn’t turn down.
“I think my skillset will complement Glasgow’s style of play – I like to play with ball in hand and carry hard.
“I can’t wait to get up and put the hard yards in every single day and earn the right to wear the jersey.”
Manjezi was encouraged by Kyle Steyn, a former Griquas team-mate who he will link up with at the Warriors who enthused the club’s culture, work ethic and its ambitions.
Head Coach Danny Wilson added: "Sintu is the type of attacking presence we wanted to add to our depth in the pack.
"It’s great to bolster our second-row options with another exciting player that brings a real carrying presence and good set piece skillset - Sintu also brings the added bonus of being able to play at six.”
Versatile Manjezi is also adept in cricket and represented Easter Province at under-19 level before turning pro in rugby. He first came to prominence in South Africa’s schoolboy ranks, captaining St Andrew’s College first XV en route to earning a place in the Eastern Province Academy.
An impressive stint in Griquas colours earned him a move to the Toyota Cheetahs ahead of the 2018/19 Guinness PRO14 campaign, where Manjezi immediately caught the eye of northern hemisphere observers.
His dynamism in the loose and set-piece expertise was a key factor in the Bloemfontein outfit earning a place in the playoffs for the first time in 2019, with only the COVID-19-enforced suspension of the league preventing Manjezi and the Cheetahs making it back-to-back playoff appearances in 2020 before a move to the Bulls.