Lions coach Michael Voss admitted the important backman had carried an injury during the week but was reluctant to provide any details.
"At the moment I don't know whether I'd really like to disclose that particular issue," Voss said following the Lions' final training session at Wesley College.
"Drummo hasn't trained all week. Whenever [a player] hasn't trained all week we've got to make sure they are fit and healthy.
"The normal process [is to give them a light week] in that situation, Jared [Brennan]'s done it before, where he hasn't trained [but played] and Michael Rischitelli has done it before [as well]."
Travis Johnstone is the team's travelling emergency, making him the most likely candidate to replace Drummond if he fails to make the team.
At the other end of the spectrum, forward Daniel Bradshaw is ready to go after spending two weeks sidelined with a hamstring strain.
Voss agreed Bradshaw's inclusion helped take some pressure of Jonathan Brown who played a lone hand up front in last week's loss to Collingwood, but added it mattered little if the twin towers did not receive adequate assistance from their teammates.
"If we don't have everyone joining in or we only get little bits and pieces from everyone then it doesn't matter what those two do – it will impact our whole scoreboard and our whole team," he said.
"It's nice to have the luxury of having Braddie back, but we also know that the others need to join in too."
Voss isn't buying into the generally gloomy outlook on the Bombers who have suffered three straight losses on the back of a mounting injury list.
With 11 wins in the bank the Brisbane Lions stand on the verge of a finals berth, but Voss maintains September action is not yet on the agenda.
"At this time of year you've got to be very careful that you're not focusing down the track, but that you're focusing on what you need to do and that’s tomorrow's [game]," Voss said.
"All the work that we've put in over pre-season, over the year becomes fruitless unless you can really finish off the year.
"The guys have done the work, but we haven't finished off the work [yet] and that's the important thing to do. They've got the necessary ability to be able to be there, but we haven't earned the right [yet] … that's why this is a really big game for us and Essendon."
