Chelsea's Antonio Rudiger says "difficult" contract negotiations and a lack of communication are the reasons behind his departure from the club.
However, Real Madrid have agreed a deal to sign the Germany international.
"I leave this club with a heavy heart. It has meant everything to me," Rudiger told The Players' Tribune.
"Unfortunately, my contract negotiations had already started to get difficult last fall.
"Business is business, but when you don't hear any news from the club from August to January, the situation becomes complicated."
Rudiger, who joined Chelsea for an initial £29m from Roma in 2017, is expected to sign a four-year deal at the Bernabeu.