Gregg Allman of the Allman Brothers Band was set to appear on “Colbert Report” and “Piers Morgan Tonight”, but instead he will undergo diagnostic cardiac testing at the Mayo Clinic’s Jacksonville campus.

Doctors are trying to determine whether Allman needs additional care stemming from his recent hernia operation

Rolling Stone is reporting that Allman, who received a liver transplant at the Mayo Clinic in 2012, will have to delay the publicity tour for his forthcoming memoir, My Cross To Bear.

“I’ve been working on the book for years and am grateful for all the support I’ve received in putting it together,” Allman said in a statement. “As soon as doctors give me the thumbs up to go back on the road, I will be heading out onto my book tour and I can’t wait to meet all of my fans.”

The Rocker was set to appear in “The Colbert Report” and “Piers Morgan Tonight”

The Allman Brothers Band summer tour is not expect to be effected by the testing, more tour dates for that tour are expected to be announced May 1st.