I go on the actual score and not "Could have been" because Wellbeck could have scored altering the course of the match. The fact that Dortmund didn't score more is a worrying sign just as it is for us against Sunderland. Either the chances will keep coming and be converted or they'll dry up. So 2-0 is what we have to go on and is not insurmountable in the second leg.
It's a six game league, TMT. No second legs.