ex-dortmund star robert lewandowski nets winner in the 36th minute .
dortmund are unable to score equaliser despite dictating second half .
bayern munich open up 10-point lead over second-placed wolfsburg .
dortmund xi vs bayern munich : weidenfeller ; sokratis , subotic , hummels , schmelzer ; gundogan , bender ; błaszczykowski , reus , kampl ; aubameyang .
bayern munich xi vs dortmund : neuer ; dante , boateng , benatia ; rafinha , alonso , bernat , lahm , schweinsteiger , muller ; lewandowski .