Left-back Sawyer is on his way back from a hamstring operation while right-back McNamee has a calf injury.
But Sturrock's squad has been boosted by the return from injury of left-back Jim Patterson, who can also play in midfield.
Sturrock - who comes up against his former club when the Owls visit - is toying with whether or not to change the starting XI that has reaped seven points from three games following Tuesday's 2-2 draw at Bristol City where Argyle let a two-goal lead slip.
Striker Emile Mpenza and on-loan French winger Nicolas Marin have yet to make their first starts for the in form Greens and will be hoping for a chance to shine.
Sheffield Wednesday captain Richard Wood and Peter Gilbert will have late fitness tests.
Central defender Wood sustained a groin injury in the midweek win over Nottingham Forest, while Gilbert has a slight hamstring strain.
Mark Beevers, fully recovered from his hamstring problem, stepped in for Wood against Forest and would be a straight replacement.
Owls manager Brian Laws has hinted striker Francis Jeffers is ready to make his first start in nine months following a serious ankle injury, but the former Everton and Arsenal striker is expected to resume on the substitutes' bench again.
Winger Jermaine Johnson missed out in midweek with an ankle injury, but could return to contention, while Wade Small (hamstring) suffered no reaction from Tuesday night and is also in the reckoning at Home Park.
Sporting Life