Amir Khan world title shot against Andreas Kotelnik has been postponed for three weeks following an injury to the Ukrainian.
Khan was due to challenge for Kotelnik's WBA Light-welterweight title in London on Saturday June 27, but the fight has now been rescheduled for Saturday July 18.
The fight will now take place at the Manchester Evening News (MEN) Arena.
Khan said: "I'm delighted that the fight is still on, and when 18 July comes I will never be more ready for him although, the postponement is a pain.
"These things happen so I have to be professional and stay focused. However, when I'm crowned world champion it will make up for it."
"Freddie Roach is adjusting my training accordingly so that I'm ready for the new date and I'm at my peak both physically and mentally."
Khan added: "I was looking forward to headlining at the O2 Arena again as I have a lot of fans in London.
"I always get a great reception there so hopefully I can go back sometime soon, maybe for my first defence.
"I had a great night at the MEN Arena against Barrera last time out and now I aim to win the world title against Kotelnik there, too."
Fans who have purchased tickets for the fight at the O2 Arena are asked to return them to their point of purchase.
If you bought the tickets from AmirKhan-Boxing.com - please call 01204 535 332
Further information on tickets can be found on www.frankwarren.tv or by telephoning the Frank Warren Promotions Box Office on 01992 550 888
