Cross Dissolve using unwanted footage

I trimmed the first part of a clip to eliminate a person walking in front of my subject who momentarily started her song. When I put the clip in the timeline and put a cross-dissolve at the end of the prior singer, the cross dissolved sucked back in the portion of the clip with the person walking in front of my subject. I tried several methods to get rid of this but can't seem to do so. Of course, without the cross dissolve the two adjoining clips are OK. Any help would be appreciated, since I really would like to use a cross-dissolve.