Geelong defender Lachie Henderson remains in doubt for the clubs season opener against Melbourne on March 25 after details emerged surrounding the extent of his off-season knee surgery. 

The former Blue has yet to begin running since undergoing a second arthroscopy which raises serious question marks over his availability for round one. 

โ€œLachie Henderson has not run since December 13, when he had another arthroscopy on left knee,โ€ Sam McClure said on SENโ€™s Time On.

โ€œHe has not been training for two monthsโ€ฆand unless something miraculous happens heโ€™s not going to be playing round one.โ€

Geelong's backline remains somewhat thin after the retirements of Andrew Mackie and Tom Lonergan and while Harry Taylor will move back to the defensive end in 2018, Henderson has been a key pillar of Geelong's defence since his arrival in 2016.