 Clapton simplifies Johnson 's guitar line and sets it to a straight eighth @-@ note or rock rhythm . He and Bruce on bass continuously emphasize the riff throughout the song to give it a strong and regular metric drive combined with Baker 's drumming . Johnson 's irregular measures are also standardized to typical twelve @-@ bar sections in which the I – IV – V blues progression is clearly stated . Clapton does not adapt Johnson 's slide guitar technique or open tuning ; instead he follows the electric guitar soloing approach of B.B. King and Albert King . However , he employs a Johnson guitar innovation , the duple shuffle pattern or boogie bass line , while singing ( Johnson only used it for two bars in " Cross Road Blues " ) . 
