Egypt's world champion Ramy Ashour has been forced to withdraw from next week's British Open in Hull after injuring his Achilles tendon.
The 28-year-old had only recently returned to competitive action following a four-month absence because of a knee-meniscus problem.
Ashour is a three-time world champion and won the British Open in 2013.
England's Nick Matthew will be seeded third behind Mohamed Elshorbagy of Egypt and France's Gregory Gaultier.
Eight-time champion Nicol David of Malaysia will top the women's seedings at the KC Stadium, with Egyptian Raneem El Welily second and England's 2013 champion Laura Massaro third.