JLS star Ashton Merrygold was hospitalised after messing up a backflip during tour rehearsals.
The 23-year-old singer, who is joined in the band by Marvin Humes, Oritse Williams and J.B Gill, suffered concussion when he landed on his head while executing the tricky move during the penultimate dress rehearsal for the band's 4th Dimension tour.
Speaking to the Daily Mirror newspaper J.B said: ''This show really has been blood, sweat and tears... and scratches. We're all injured. One of our dancers slipped a disc, one had a really bad neck injury and one a knee injury.
''Then Aston fell on his head which was pretty nasty.''
Aston added: ''It's been full-on. As well as landing on my head, I busted my knee and J.B. did his, too.''
However, this isn't the only injury Aston has suffered as a result of the tour, as he also ''nearly drowned'' during a tricky water stunt.
Marvin further explained: ''Aston also nearly drowned during one of the water stunts. Our lives have definitely been at risk.''
Despite risking life and limb to put on the show, the band have promised fans will enjoy a ''proper event''.
Marvin added: ''We wanted to step it up, so we've gone crazy. It's a show, not a concert. We wanted it to be a proper event.
''I've got bruises and scratches all over my body.''