Nearly a year ago Robert Johnson with 'Wish Upon A Star' was the Friday STAR TRACK. I said the song's riff reminded me of something but couldn't recall what it was. (You'll probably need to refresh your memory at this point > http://billblogs2.blogspot.co.uk/2016/07/its-1978-and-im-in-wine-bar-in.html )
Well, a few weeks back I came across this track from roughly three years previous to that Robert Johnson's release. It's that guitar riff !
During the mid 70s the radio played a lot of Nils Lofgren, mostly 'live' material that wasn't available on an official album release, only as a limited promotional record called "Back It Up !! - Nils Lofgren Live - An Authorized Bootleg".
I've found on YouTube two slightly different versions. One appears to be the original take from this bootleg LP - the other is from the Old Grey Whistle Test in 1975, re-broadcast on BBC4 in a Guitar Heroes compilation show. Both worth a look… and there's that riff

The sound on the OGWT recording is not as good, but the track is longer…