BORUSSIA DORTMUND ace Neven Subotic has paid thanks to his mentor Jurgen Klopp.
And his agent has refused to rule out that the defender could move to England this month after his summer transfer fell through.
Current Liverpool boss Klopp signed Subotic at the start of his successful Dortmund tenure.
The pair went on to claim five major honours together at the Westfalenstadion before Klopp decided to call time on his career in Germany and make his move to Anfield.
Subotic says Klopp played a key role in his development as a footballer and will be forever grateful for his guidance.
The 28-year-old told The Daily Star: “Klopp has been my mentor for nine years, he supported me, encouraged me, had trust in me.
“With him and Dortmund I had the most amazing time. For that I am forever thankful.
“He was and is an important person in my life and I owe him a lot.”
Subotic was heavily linked with reuniting with Klopp at Liverpool during the last transfer window.
Arsenal, Everton and Middlesbrough were also said to be interested in the Serbian centre-back but a potential move to the Premier League failed to come off.
His agent, Frieder Gamm, has revealed that a number of European clubs looked into a deal over the summer but an untimely injury blow put an end to a possible transfer.
Gamm told Starsport: “There were several options from all over Europe last summer but the rib operation had priority at that time.
“There was serious interest from several clubs but due to the operation a transfer did not take place.”
Asked if Subotic would be interested in moving to England during the current transfer window, Gamm replied: “Everything is possible in football.”
Aitor Karanka’s Boro are said to be looking into a deal for Subotic again this winter.
The defender, who scored twice in 36 caps for Serbia before his international retirement in 2013, is currently playing for Dortmund’s second team as he looks to regain his full form and fitness.
The ex-Mainz ace has made over 250 appearances for the BVB.