Sir Bobby is though confident that the Welsh striker will be fit for next week’s Champions League clash with Partizan Belgrade or Djurgardens.
"Craig mentioned it at half-time and we told him not to progress it, not to develop it and at the first signs of it not being right to get off, which he did," explained Sir Bobby.
"It needs settling down for two or three days, so there's a good chance that he'll be okay for Wednesday.
"It's seven days away, so it's fine. I don't think we'll test it out at Workington Town on Friday."
It wasn’t all bad new though as Alan Shearer continued his sparkling pre-season form with a goal in each half, only for the German champions to equalise twice through Owen Hargreaves and Claudio Pizarro.