Sebastian Kehl says Shinji Kagawa would be welcomed back to Borussia Dortmund with open arms.
Douglas has described his arrival at Barcelona as the pinnacle of his career ahead of their visit to Villarreal on Sunday.
Germany coach Joachim Low says he still fancies a return to club football when he eventually does bring an end to his term as national team coach.
Speaking after putting pen to paper on a contract which will see Low reach a decade of service at Euro 2016, the 53-year-old said he will not be able to walk away from the game if he does not sign another contract as Germany coach.
"Looking to the future, you know that this collaboration will come to an end sooner or later," he said at a press conference on Friday.
"I can imagine coaching a club again at some point. I love this job too much to think about retiring, although at the moment I am focused on the Germany job."
In seven years since taking up the reins from Jurgen Klinsmann, Low has led Germany to one final and two semi-finals in the last three tournaments.
The expectations will be equally high in Brazil next summer and Low suggested Germany have got to be among the favourites.
"I do think that there is nothing but the title for us (in Brazil), but then that seems disrespectful to the other nations," Low said.
"Spain have won the last three titles, Brazil are playing at home and they won the Confederations Cup - these and other nations have top quality.
"But I do think that, given what we have done in the past four years, we have got to belong among the favourites."
With nine wins out of 10 qualifying games, Low has every right to be confident.
Germany have shown time and time again under the much-travelled coach, who lists Stuttgart, Fenerbahce and Austria Vienna among the clubs he has led, that they are a force to be reckoned with, even if they have effectively run out of gas on the brink of glory.
Twice beaten by Spain in 2008 and 2010, they were outclassed and outplayed by Italy at Euro 2012 when they seemed odds-on for glory and Low has consequently learned never to be satisfied.
"Satisfaction is a word which I have scrapped from my vocabulary," he said. "Even in games when you feel everything was spot on, as a coach, you are never 100 per cent satisfied.
"Obviously we were not satisfied with the European Championships last year, even if we did play some very good games. This is a situation I experience constantly as a coach."
Pressure also always accompanies a coach and Low is no different.
According to the Bild newspaper, the new two-year contract extension he signed on Friday includes a clause which allows either the German Football Association (DFB) or Low to terminate the contract without any notice should Germany fail to live up to expectations at next summer's World Cup.
"It all depends on how you get knocked out," said the last man to guide Germany to the World Cup title, Franz Beckenbauer, to Sky Sport News.
"If you get knocked out playing exciting football, then there's nothing to worry about.
"But Joachim Low has his team under control and Germany will play attractive football."
If they fail to do so, Low is not likely to be short of offers next summer, and probably not only from the Bundesliga either.