David Pocock, Tatafu Polota-Nau and Sitaleki Timani have been ruled out of the Tests in Brisbane, Melbourne and Sydney due to injury, while doubts also exist over the fitness of Scott Higginbotham, Digby Ioane and George Smith. Added to the list of absentees is utility back Kurtley Beale, who is undergoing treatment for alcohol-related problems.
World Cup-winning fly-half Lynagh, who played for Australia in their 2-1 series defeat to Finlay Calder's 1989 Lions, told talkSPORT: "The Lions could win the series 3-0, yes."
He continued: "Australian teams in the Super 15 tournament have had quite a few injuries to key players, people like Scott Higginbotham, Digby Ioane and a number of other players who would have appeared in the Test series.
"That's hurt Australia and their problem is that they don't have a huge amount of depth. They have 20-odd players who are strong but as soon as you scratch the surface, they become a bit thin.
"Having seen the Lions beat the Barbarians in Hong Kong last weekend, albeit against a weaker opposition, they are a very strong squad with lots of seasoned players. They are physically big and even as an Australian, I'm starting to get a little bit worried about the Test series coming up."
The Lions, who face the Western Force in Perth on Wednesday, launched their 2013 tour with a Welsh-inspired 59-8 rout of the Barbarians.
Including Saturday's opener in Hong Kong, they have six fixtures to prepare for the opening Test at Suncorp Stadium on June 22, and Lynagh believes that schedule places them in a stronger position than Australia.
"We talk about how hard it is for the Lions to come together with all the different nations and the fact they have to gel quickly, but Australia have no warm-up matches," he said.
"They might have played together before, but sometimes people are injured and that sometimes means that they won't have played together. So despite the Lions saying that it's difficult, they will be better prepared than Australia."