Help with staining pine

Aloha all,

Okay, so this isn't about staining a Tiki, but I could really use all you expert woodworker's help.

Recently my wife and I had a new patio door installed. The part of the door that is on the inside was unfinished Pine. We had a cabinet maker come out and stain the door for us, but they failed to use pre-stain prior to staining (which the door manufacturer HIGHLY recommends). Now the door has major spots of blotchyness.

ALSO, he has already put on a very thin coat of polyurethane.

My question is this: Is there anything I can still do to fix this? Is it possible to sand the door down and apply pre-stain then stain it again - or would this just make it worse.

I would greatly appreciate any help you could give me.

Sanding it down to bare wood may be hard but if possible it is the way to go. Also you can find polyurethane With Stain mixed in. You could try a few coats of that but you may still end up with the blotchies.
My recomendation is the sanding it down method. sand down to bare wood and then use a pre stain sealer, at least 2 coats. Then stain it again. However with pine, anywhere you have end grain showing will still end up darker. Pine is difficult to stain evenly so you may want to try the polyurethane with stain mixed in. Try a small spot before finishing the whole door.
Hope this helps.

Benzart,

That is a huge help. I'll try to sand it down this weekend. You've been a huge help.