"We still keep in touch," he told Bundesliga.de. "It's a bit difficult to speak to him directly, largely because his German hasn't dramatically improved while he's been in England.
"Talking to him on the phone isn't what you'd call a piece of cake. I often have a few words with Shinji's agent, Thomas Kroth, as well. Believe me, I'm always right in the picture about what the lad's up to."