Kevin Wimmer admitted it had been a wrench to leave Cologne, but says the opportunity of playing for Tottenham Hotspur was too big to miss.
The 22-year-old central defender completed his move to the Premier League club on Friday for an undisclosed fee having already been given a send-off by the Cologne fans prior to their last game of the season, when it was already clear he was leaving this summer.
"Tottenham is a great chance for me," Wimmer said on the club's official website. "It is nevertheless not easy to leave Cologne.
"I had a fantastic, successful time in Cologne with promotion and then staying up and I would like to thank from the bottom of my heart the coaching team, my team-mates and the whole club for the faith and support they showed me.
"Cologne and their fantastic fans will always remain something special for me."
The Bundesliga club are also sad to see Wimmer go, but they said the offer from Spurs was too good to refuse.
"Kevin has come on leaps and bounds in the past three years and he has become an international player," said Cologne's general manager Jorg Schmadtke.
"Of course we regret the fact that he is leaving, but we can also understand that he desperately wanted to take this opportunity to move to a big London club steeped in tradition.
"We were able to find an acceptable solution for all parties in our negotiations with Tottenham."
The Austrian played 72 times for Cologne, scoring two goals since joining from LASK Linz in 2012.