"Jonathan has trained for the first time with us and he did very well," said Sir Bobby.
"But because he does not play for us until we entertain Chelsea on March 1, I have told him there is no need to take any chances and not to rush back.
"He cannot play against Leeds a week on Saturday and this is the reason I will not take him to Germany with the rest of the squad on Sunday for next week's Champions League game with Bayer Leverkusen.
"If he had been able to play at Leeds I would have taken him to Germany, but I feel there is more benefit to him to stay at home and train."