Liverpool manager Jurgen Klopp privately called Kostas Tsimikas to declare his interest in bringing him to Anfield, Greek media outlet Sportime reported.
Klopp reportedly told Tsimikas: 'The decision is yours. We want you, you fit very well in our project and in how we want to play.'
The 24-year-old left back made 46 appearances for Olympiacos in all competitions last season, as they won their 45th Greek Super League title.
Liverpool's first choice was Jamal Lewis but Norwich City did not accept Liverpool's 'low-ball' attempt offer of £10million. According to sources, they demanded close to £20million.
Jurgen Klopp also admitted Liverpool were tracking new signing Kostas Tsimikas for "a long time" and hailed the Greek international's "attitude and mentality." Speaking to the official Liverpool website, he said: "We have watched Kostas for a long time and are really happy that he has joined us."
"He is a very good footballer with an attitude to win and to compete, and I really like his mentality. It fits perfectly with the mood and the desire we have in our dressing room already (...) He has showed already at a young age he can experience football in a different country and do well - and he has been a big part of the success Olympiacos has had to win their title this season and in their European campaigns," Klopp continued.
Financial details were not given, but British media reported Liverpool paid £11.75million for Tsimikas.
The defender will wear the No.21 shirt for Liverpool.
“My brother is a Liverpool fan, so he pushed me to come here,” remarked Tsimikas after the transfer was unveiled by Liverpool.
“As a child, I supported Liverpool. For all of my family and my brother, I am really happy to sign for this club. My brother will be satisfied when he sees the pictures of me joining Liverpool,” the 24-year-old added.