Last season's European Tour number one Robert Karlsson, who has been out of action since May, will not be returning for at least two more weeks.

The Swede has been suffering from a blister behind his retina, thought to be stress-related, and has his next doctor's appointment is on September 3.

Having missed the last three majors, Karlsson played the pro-am before the SAS Masters in Sweden a month ago, but was still suffering problems with his depth perception.