America's Shaun Micheel was burgled ahead of his second-round meeting with Vijay Singh at the World Match Play.
The USPGA champion's rented house on the Wentworth Estate in Surrey was broken into overnight on Thursday.
He lost about $2,000 as well as credit cards and his manager's suitcase.
Micheel, who was in the house at the time of the robbery, said the police arrived two hours later at 0245BST.
They left at about 0330BST, leaving the 34-year-old with little time for sleep ahead of a 0900 tee time for his match against Singh.
Micheel said: ""It was quite scary because we were in the house when it happened, just another part of it.
"I guess people are more brazen about that sort of thing round here.
"But it didn't give me the best feeling or the greatest start to my Match Play participation. It was a rough day."