Mystery Baseball Game Bird

A reader has submitted help with id.  Since I don't live in Missouri nor attend many baseball games, I thought one of you readers could help our girl Veronica.  Here is her description: I hope you don't mind me asking you for help, but but I have been trying to identify a bird since last July.  Unfortunately I don't have a picture. I saw him at a baseball game in July 08, in Kansas City, MO at the Royals Stadium.  He waited until dusk to show up, when the big lights came on, sat on a wire above the seats and then proceeded to swoop and drop down almost touching the field to catch bugs in the air.  It was amazing.

He appeared to have yellow on his belly, and his back feather tails spread out when he flew.  He was very sleek in shape, and looked long when perched on the wire.  I never heard any song from him.   Because of the stadium lights I couldn't see any of his markings, just the yellow when he would land above us.

I went to a game last week to try to find him again, but it was so windy and sprinkling, no birds were in sight.  I have looked on line and in books and he might be one of many birds to my untrained eye.  But I thought maybe you would know of a particular type of bird that likes stadiums-ha!

Coloring wise he could be a Baltimore Oriole, Tropical Kingbird or he kinda of looked like a Scissored Tailed Flycatcher?(His tail really stood out as different/long while sitting on wire). The bird I saw appeared to have a longer beak than the Nighthawk.  I remember looking at the beak because it wasn't short and stubby like a Robin's. It was a little longer, thin/tapered-but not curved.

My husband thought I was so funny, I was watching the bird and not the game.  But it was so amazing how he was doing his thing, in the middle of this big crowd, and a ball flying around the place.  At one point he dropped so low I thought he was going to hit a player on the head.  haha  Sometimes he would go almost go to the ground.

My guess is a western kingbird. But what about you, readers?  Has anyone been out this stadium and seen this bird?