GEELONG coach Chris Scott has refused to rule out further surgery for key defender Lachie Henderson as he continues to battle a knee injury.

Henderson ran laps away from the main group at Friday's main training session with no timeframe set for a return after he underwent surgery in December. 

A fortnight ago Scott hinted that Henderson had "turned the corner" in his recovery, however the final stages to reach full fitness continue to provide a stumbling block.

"I'm not sure I got that right that he'd turned the corner," Scott said on Friday.

"I did say that, but it just seems to continue to frustrate that issue because it's not clear exactly when he'll get back.

"It's been also a little hard to read because he's been functioning at a reasonable level but the last, whatever it is, 10 or 20 per cent hasn't been forthcoming.

"There's no real update there other than to say we don't expect to have him back in the next few weeks."

When asked if Henderson would potentially require surgery if his rehabilitation continued to stall, Scott suggested it was a chance.

"I think so, but I don't really know," Scott said.

"It's a situation I don't get really too involved (in), I just don't have too much to add. I couldn't rule it (surgery) out."

Henderson's continued woes coincide with Harry Taylor's plantar fascia injury he suffered in round one. 

Taylor trained indoors on Friday with no timeline set for his comeback.

Makeshift utility Mark Blicavs trained with the defensive group, as did former North Melbourne forward Aaron Black, in a sign he could be thrown into the mix in future weeks.

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