The veteran backman suffered an injury to his left hand early into Saturday's AAMI Community Series clash with Hawthorn in Tasmania, however Grimes was able to continue playing throughout the match.
The club has now confirmed that Grimes will be in a race to play against the Blues at the MCG in 10 days' time, having required surgery on his injured thumb after suffering ligament damage.
Grimes' absence is set to compound the Tigers' injury woes from this pre-season, with fellow triple premiership defender Nick Vlastuin (hamstring) also no certainty to lace up the boots for Richmond's season opener.
Gun midfielder Kane Lambert is unlikely to feature in the early rounds of the season and could be sidelined for a lengthy period should he undergo surgery on a hip issue.
Richmond are also continuing to assess Jack Graham's fitness in the coming week, with the midfielder having battled with hip, back, glute and hamstring issues in recent months.