Murray is playing in Australia under his protected ranking of world number two, which is used to help players who have suffered long-term injuries.
"The hip is incredibly difficult to come back from for especially a tennis player and someone that has worked as hard as he's worked, put the miles on", ESPN tennis pundit Patrick McEnroe said.
Britain's Andy Murray will open his Australian Open campaign against Spain's 22nd seed Roberto Bautista Agut.
Serena Williams, who won the Australian Open in 2017 while pregnant with daughter Alexis Olympia, returns as the 16th-seeded player after missing last year's tournament.
Last year's semi-finalist Kyle Edmund looms as a possible fourth round match-up for the Spaniard, who could then face big-serving Kevin Anderson in the quarter-finals.
Looks like Kyler Murray could be headed to the National Football League draft
The quarterback class is seen as weak, which would give Murray a good chance to go higher than he might have in other years. Murray was the first athlete in history to be selected to the Under Armour All-American game in both football and baseball.
A supporter of the 31-year-old wrote on Instagram saying how much they enjoyed Murray's practice match with Novak Djokovic on Thursday. One more here would see him follow Jimmy Connors as the only man in the Open era to hit three figures, as well as taking him past Djokovic and Roy Emerson at Melbourne Park.
Roger Federer's bid for a third successive Australian Open title will begin against world No. 99 Denis Istomin, while top seed Novak Djokovic will face a qualifier in the first round.
"I'm so close, I'll give it a go, " Federer said. If it would happen defending this title, I would gladly accept it.
US Open champion Naomi Osaka is at four while Sloane Stephens, who also slumped out of Sydney early, is at five.
Wozniacki finally broke her grand slam duck 12 months ago but struggled through the rest of 2018 before revealing a diagnosis of rheumatoid arthritis.
Defending Australian Open men's and women's champions Roger Federer and Caroline Wozniacki have attended the Australian Open 2019 Official Draw at Margaret Court Arena on Thursday night, where the opening-round matchups for the year's first Grand Slam tournament were revealed. For me it's just taking it day by day, doing the right things, taking even better care of my body.