Not a swallow

On our walk this morning we encountered a large flock of swallows gathering in the fields behind one of the farms. Swooping as they caught late summer insects prior to migration they were almost impossible to capture. 

I have hundreds of failures to prove it... 

This fellow was with them though, and while he's not as sharp as I'd like I did like his wing display.  If push came to shove, though, I'd not be sure enough of what he is to write it here. One of you will be confident and tell me...

Addendum: It's a juvenile goldfinch. Here's a good shot bu someone else.