The Allman Brothers Band are the link between the southern rock sound and Grateful Dead style jam bands, and one of the similarities between TABB and the Grateful Dead is they both had two drummers. For TABB the drummers were Jaimoe Johanson and Butch Trucks, who I was disappointed to learn died recently.
Songs like "Whipping Post" or "In Memory of Elizabeth Reed" would be a more obvious tribute, but I'm choosing the slightly less popular "Dreams" from their eponymous 1969 debut LP. I've already established the cultural importance of Molly Hatchet for Danette and me, so it won't come as a surprise that I first learned of this song via Molly Hatchet's cover, which they retitled "Dreams I'll Never See", from their 1978 debut LP. They do a good cover, and though I first heard their cleaner and streamlined version, over time I've come to appreciate the fuzzy/groovy original more.
The Allman Brothers Band - "Dreams"
Molly Hatchet - "Dreams I'll Never See"