Stuart Swanlund, the lead guitarist for The Marshall Tucker Band, died on Monday, Aug. 4 at 54. According to Publicist Don Murry Grubbs Swanlund died in his sleep of natural causes at his Chicago home.

Swanlund had been a member of the Marshall Tucker Band since 1985 after the band had regrouped from a former hiatus. While Doug Gray formed the band in 1972 and remains a key member, Swanlund was the longest running member.

As the group is best known for their 1977 hit single "Heard It In a Love Song," The band's blend of rock, rhythm and blues, jazz, country, and gospel helped establish the Southern rock genre in the early 1970s

The Marshall Tucker Band has since continued recording and touring by playing between 150 and 200 shows per year.

Swanlund's funeral will take place Saturday at the Good Shepherd Memorial Park in Boiling Springs, S.C., according to the Denver Post.

He is survived by his sister, three grandchildren, a son, William "Billy" Swanlund, and his lifelong partner, Stacey Schmaren.