Watch the The Staple online guitar lesson by Jeff McErlain from Solo Factory: Chicago Blues
I called this lick The Staple for obvious reasons, it is a staple of blues, jazz and rock guitar. I first heard the lick from Eric Clapton on Crossroads and also realized Billy Gibbons uses this one quite a bit especially in the tune La Grange. Pay close attention to my fingering on this one as I think it works best for sliding from the pentatonic positions that were using. A fun side note to this lick is it works great as a C major lick as well. You just want to be careful that you resolve it correctly, an A note is not always the greatest choice on a C major chord.