The midfielder signed with Hibs after successful trials this week and said: "I was very good friends with Grant and he had nothing but praise for the club. He made me feel very welcome when I went to Melbourne so he was one of the first people I talked to.
"I was over there and I just thought that, at 25, my career would just pass me by there. It's hard to go anywhere from there.
Keenan admits he has strong ties to Edinburgh.
"My mum is from Edinburgh and my uncle Iain is a big Hibs fan and used to talk about them a lot so there is some history there," he said. "My uncle drove me around the stadium when I was younger and told me all about the club, but he was too tight to take me to see a game!
"I also knew Filipe Morais and Yves Ma-Kalambay from my Chelsea days as well so in many ways it was quite easy to fit in."