Gallagher left Oasis last August after arguments with his brother Liam
Musician Noel Gallagher has described the moment he was attacked on stage in Toronto, telling a Canadian court it was akin to being "hit by a bus".
The former Oasis star said he had been told he may never recover from the rib injuries he sustained during a gig in September 2008.
Gallagher's victim impact statement was read out during a sentencing hearing for his attacker, Daniel Sullivan.
Sullivan, 48, pleaded guilty to assault causing bodily harm last November.
His sentencing, due to take place on Tuesday, has been postponed until 21 April.
Gallagher, who was not at the hearing, said he was completely taken by surprise when Mr Sullivan ran on stage and pushed him over.
"I ended up in a heap on the floor," he wrote. "I had no idea what had happened."
Gallagher, who was performing with his former band Oasis, tried to continue but was taken to hospital after experiencing "acute pain".
A subsequent examination in London revealed he had sustained three broken ribs in the attack that kept him "in some degree of pain" for eight months, he said.
Gallagher said the attack forced Oasis to cancel gigs and promotional appearances, affecting the sales of their Dig Out Your Soul album.
Mr Sullivan, of Pickering in Ontario, has claimed he was drunk during the incident and has no idea how he got backstage.