Essendon captain Dyson Heppell and star defender Michael Hurley headline a host of Bombers undergoing post-season surgery.
Heppell battled pain in the growth plate of his left foot in the latter half of the season but will have a procedure in the coming days.
The 27-year-old is likely to integrate into main training in early December.
Sustaining a shoulder injury against Collingwood in round 23, Hurley underwent a shoulder reconstruction on Monday and is expected to train fully post-Christmas.
Hurley's round 23 injury will delay his return to main training in pre-season. (Photo: AFL Photos)
Orazio Fantasia will also have a delayed start to pre-season, requiring a hip arthroscopy in the coming weeks.
The lively forward is earmarked to join main training in January.
Despite making a successful return this season from a severe ankle injury suffered in the 2018 JLT Community Series, defender Marty Gleeson is booked in for an ankle arthroscopy this week, but it is not expected to interrupt his 2020 pre-season.
Recently re-signed youngster Matt Guelfi underwent surgery to repair his lateral meniscus and will begin running in approximately seven weeks.
Veteran David Zaharakis (syndesmosis) also required surgery in late August and is expected to begin pre-season with the main group.
2018 draftees Irving Mosquito (hamstring) and Noah Gown (foot stress fracture) went under the knife recently after succumbing to season-ending injuries.
Mosquito will spend the next three months in rehab, while Gown will commence running on an Alter-G treadmill in three weeks and is expected to start pre-season as normal.
Hardworking forward Mitch Brown suffered a low-grade calf strain in the Bombers’ season-ending loss to the Eagles. It is not expected to greatly interrupt his off-season program.
Zac Clarke is due to commence running in five weeks, after sustaining a stress fracture of his fibula late in the season.
The Bombers will begin pre-season in November.