The 29-year-old, who had minor knee surgery in late November, will not be rushed into pre-season fixtures by the Essendon fitness staff.
"David is in some doubt in terms of round one of the NAB Cup and is probably not really near that stage just yet," club football manager Paul Hamilton told essendonfc.com.au this week.
"However all eyes are certainly on round one of the season proper rather than NAB Cup for David."
Meanwhile, young Essendon half back Anthony Long will be managed cautiously as he attempts to recover from a hamstring tendon injury that required surgery.
The 2009 draftee battled hamstring problems last year, missing the last eight games of the VFL season.
"For us, Anthony is a long term player and it has been a gradual recovery process with him, however he is certainly building up to full training, which is positive news for a guy who we have a lot of hope and faith in," Hamilton told Bomber TV.
Tayte Pears (foot), Taite Silverlock (foot) and Michael Ross (hip) are all reported to be progressing well from their respective problems.
