Bayer Leverkusen midfielder Hakan Calhanoglu tried to stop Heung-min Son joining Tottenham last summer, reports the London Evening Standard.
The South Korean international spent two productive years at Leverkusen, scoring 29 goals in 87 appearances for the Bundesliga club.
Calhanoglu was shocked by Son's departure and told Kicker in August 2015 that he attempted to reverse the forward's decision.
"It's a bit disappointing. I tried to reach him but I could not get hold of him," the Turkey international conceded.
"The whole team is disappointed, but it's not his fault - he's a good lad. I believe that he's been badly advised.
"We were there for him always - that's why we are sad."