He delivered a moving eulogy at Hughes' funeral in December 2014 and dedicated Australia's 2015 World Cup final win to the team's "little brother and teammate Phillip Hughes".
Clarke said he is hoping to spend all of Friday in hospital with his wife, Kyly, and their newborn daughter, Kelsey Lee, who remains in special care after being born five weeks early.
But he insists the day is not about him.
The former skipper said he will be thinking of the Australian cricketers playing against New Zealand on Friday during the day-night Test match on Adelaide Oval.
"It's going to be a really tough day and I think the guys playing are going to do it tough," he said.
"I think it's really important that we continue to support the Hughes family and show our respect there."
Clarke said he regularly speaks to Hughes' sister Megan and commended the family on the release of their official biography detailing the young cricketer's life.
"I think the book gives a really good indication of the type of person Phillip was," he said.
"His family should be really proud."
- AAP