Trevor Immelman and Robert Karlsson, last year's Masters champion and last year's European number one, have both withdrawn from this coming week's Barclays Scottish Open at Loch Lomond.
South African Immelman, who has been battling tendinitis in his left wrist and elbow, did not compete throughout June and has not had a top-10 finish all season.
Swede Karlsson's last tournament was the European Open at the end of May. He has been diagnosed with fluid behind the retina of his left eye - which is affecting not only his vision, but also his balance. It remains to be seen if they are fit enough to play in the Open Championship, starting at Turnberry on Thursday week.