The US Open is marking the 25th anniversary of the 9/11 attacks on Friday, with Arthur Ashe Stadium lit blue overnight and American flags flown at half-mast in memory of the 2,977 people killed. Former world number four James Blake, who was born in New York and was competing at that year's tournament, has told BBC Sport that the attacks "shattered the guise of safety" felt by many Americans and professional tennis players, who often felt insulated within the sport's "travelling circus" of international competition.

Blake was in Augusta, Georgia, for a medical test on the day of the attacks, while his father was in New York; overloaded phone networks meant an anxious wait before he learned his father was safe. With flights grounded, Blake drove from Augusta to Tampa, and found it difficult to board a plane to his next tournament in Hong Kong a fortnight later. He credited the resumption of sport, including President George W Bush's ceremonial first pitch at a Yankees game, with helping restore a sense of normality; this year's commemorations include a minute's silence before Friday's men's singles semi-finals and a flag ceremony featuring singer JoJo.