"He was so young, just 36 years of age".
The former midfielder enjoyed a distinguished career that saw him line out for 12 professional clubs in seven different countries, including Celtic, Manchester United, Leeds United, Sunderland, Hibernian, Perth Glory and Cork City.
Miller's first club Celtic also paid tribute, as did a range of former teammates.
The Championship club wrote: "We are saddened to hear this evening that former #SAFC midfielder Liam Miller has passed away. Our thoughts are with his family and friends at this time".
Reports emerged in November that Miller had been battling pancreatic cancer and was receiving treatment in the United States, where he played for Wilmington Hammerheads in 2016.
"My thoughts and prayers are with his family and friends". He is survived by his wife Clare and his three children Kory, Leo and Belle. We extend our condolences to our friends in the FA of Ireland and to Liam's family and friends.
He added that those who love and support Irish sport "will keenly feel his loss".
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Celtic, where Miller spent four years, will wear black armbands in his memory during their William Hill Scottish Cup match against Partick Thistle on Saturday. "Our thoughts are with his friends, former teammates and family at this time".
Former Sunderland team mate Kevin Kilbane wrote on 'Sad hearing the bad news that Liam Miller has passed away this evening, taken far too soon by a terrible disease.
"The news, we heard about it just recently, we didn't know how bad it was".
A first senior hat-trick for James Forrest yesterday seemed to have a poignancy as Miller's life was commemorated with Forrest also a homegrown Celtic player who joined the club's academy the year Miller made his senior breakthrough for the Glasgow side. "Such tragic news. What a gifted footballer he was and a true gentleman http://too.RIP Liam".
Ex-international teammate Kevin Kilbane said, "Sad hearing the bad news Liam has passed away, taken far too soon by a terrible disease".
"He was an unassuming young man off the pitch but he was a brilliant player on it".