Snyman only lasted seven minutes on his debut appearance for Munster, injuring his knee as he landed after contesting a Leinster lineout.
Lock RG Snyman, who arrived in Ireland after spending the early part of 2020 in Japan, had been chosen for his first appearance with Munster.
The Rugby Championship is set to be played in New Zealand on a condensed six-week scheduled across November and December.
Munster have their new signings training in Limerick, including Springbok RG Snyman, but pandemic safety measures mean they have yet to meet the full squad.
The Bulls' bid for Super Rugby honours has taken an early hit, with the news that one of the stalwarts of their pack RG Snyman set for a spell on the sidelines.
It was just minutes into his Munster debut that RG Snyman, the Springboks lock, did his ACL last August but his rehab has now stepped up.
Handre Pollard suffered an ACL injury in September with Montpellier but the Springboks out-half is on the road to recovery.