'Positive signs' on hospitalised Australian cricket great Martyn
The 54-year-old, who played 67 Tests between 1992 and 2006 and 208 one-day internationals, fell ill while lying down last week and was rushed to hospital.
He was diagnosed with meningitis -- an inflammation of the membranes surrounding the brain and spinal cord.
"Thank you everyone for the heartfelt love and wishes and care for Damien as he goes through a challenging time," fellow Test great Gilchrist said during a Big Bash League game broadcast on Thursday evening.
"He's still in hospital. There'll be more details coming out as they come to hand but certainly in the last 24 hours some positive signs are the indications coming out of the various tests he's having."
A who's who of cricket greats have posted messages of support, including former England skipper Michael Vaughan and Indian legends Ravichandran Ashwin and VVS Laxman.
Known as one of the game's great strokemakers, Martyn became a key figure in Steve Waugh's all-powerful Australian side, hitting 13 centuries and averaging 46.37.
He was also part of the Australia team that won the 2003 ODI World Cup, cracking 88 not out in the final against India in a match-winning partnership with Ricky Ponting.
Martyn retired in 2006 during the Ashes series and had kept a low profile since.