Watch the The Stumble: Ex. 4a online guitar lesson by Andy Aledort from Kings of Blues & Rock Vol. 8: Freddie King
Freddie King had a lot of hit records with instrumentals, such as the time-honored "Hideaway," as well as "San-Ho-Zay," "Sen-Sa-Shun" and "The Stumble," the latter of which has been covered brilliantly by the British blues greats Peter Green and Jeff Beck.
"The Stumble" is a blues shuffle in E with an interesting chord progression that starts on the IV (four) chord, A7. In this example, I begin with a catchy lick that Freddie frequently employed, bending the minor third, G, up one half step to G# while also fretting a B above the G. The riff across bars 5 and 6 offers an interesting way to play over the IV chord, as this twist on the "B.B. box" makes reference to E major pentatonic (E F# G# B C#), the E Blues scale (E G A Bb B D) and an Aadd9 arpeggio (with the first three notes in bar 6, C#, E and B).