trucks Derek Trucks (left) and Warren Haynes of the Allman Brothers Band trading shots (Photo: Dan Rys)

By now, catching the Allman Brothers Band during its annual Beacon Theatre run and NOT seeing a surprise guest or two waltz out on stage would be a bigger shock. The yearly residency, generally held in the early Spring, has seen such legends as Eric Clapton, Levon Helm, B.B. King, Peter Frampton, David Crosby, Steven Stills, and dozens of others grace the stage alongside the Allmans, re-imagining such songs as "The Weight" (which Duane Allman recorded with Aretha Franklin in 1969) and reviving others such as "Layla" for sellout crowds.

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This year, the 40th anniversary of their classic third studio album Eat A Peach, the band has brought out jazz luminaries Randy Brecker and Bill Evans, Wilco's Nels Cline, and singer Grace Potter, to name a few, and also added in an acoustic-only section to kick off their second set, a rarity for a group usually more associated with high-flying electric guitars.

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Wednesday night, the band opened the show with former New York Yankees center fielder and jazz guitarist Bernie Williams on guitar for "One Way Out," later bringing out the Juke Horns and blues singers Ruthie Foster and Susan Tedeschi, the latter who is the wife of current Allmans guitarist Derek Trucks and winner of this year's Best Blues Album Grammy with her Tedeschi-Trucks band alongside her husband.

allman Gregg Allman taking up his customary position behind the organ. (Photo: Dan Rys)

oteil Bassist Oteil Burbbridge. (Photo: Dan Rys)

stage The Allman Brothers Band on stage Wednesday, March 21. (Photo: Dan Rys)