US Open champ Simpson out of British Open
The American has pulled out of the Major, this year being staged at Royal Lytham on the coast of north-west England, because his wife is due to give birth in two weeks' time.
A brief statement issued by tournament organisers said: "Webb Simpson, the 2012 US Open Champion, has withdrawn from The Open Championship due to family reasons."
Earlier this week Mark O'Meara, the 1998 British Open Champion at Royal Birkdale, withdrew due to injury. Meanwhile Australia's Jason Day who has opted to stay at home to look after his newly born child.
Organisers said none of the absent trio would be replaced in the field "at this time".
In 2008 Tiger Woods was unable to play at Birkdale after he underwent knee surgery immediately after his 14th major victory in the US Open at Torrey Pines.