Frontman Steven Tyler has been named as the injured Aerosmith band member, who has cost the rockers three shows on their U.S. summer tour with ZZ Top.
Details of what ails the singer have not been released, but, in a post on his Twitter.com page, bandmate Joe Parry asks fans to "Pray 4 Stevens speedy return (sic)."
The band postponed their 1 July (09) show in Ohio and concerts in Pennsylvania and Virginia over the weekend (03&05Jul09) due to an unspecified "band injury".
Perry has apologised to fans via Twitter, stating, "It really bums me out (to postpone shows)."
Reports suggest Tyler may have injured his leg during a concert on 29 June (09).
Aerosmith's 7 July (09) show in Raleigh, North Carolina is billed to go on as scheduled.
The concert will be the first to feature guitarist Brad Whitford since he underwent surgery following a car accident. Bobby Schneck has been filling in for Whitford.