Essendon veteran Cale Hooker will miss the start of the season and potentially the first month of the Bombers' campaign, after suffering a calf injury at training.

Hooker didn't play in the Bombers' opening JLT Community Series game but was scheduled to face Geelong this weekend, although he'll now be forced to watch on from the sidelines.

Essendon's physical performance manager Justin Crow said Hooker would be looking at a four to six week recovery period given the nature of the injury.

โ€œCale was doing the last training session before he was due to return for JLT (game) two,โ€ Crow told the club's website on Tuesday.

โ€œUnfortunately for Cale, heโ€™s picked up a soleus injury โ€“ a calf strain โ€“ that will cost him six weeks.

โ€œCale had been doing everything right, heโ€™s a professional.

โ€œItโ€™s disappointing news for us and him, but weโ€™ll have to get back to rehab and keep building him up towards an early-season return.โ€

Crow also touched on Dylan Shiel's quad injury, although the new Don is expected to face Geelong on Thursday after pulling up well.