Staring 8 July, the US Department of State says nearly all non-immigrant and non-diplomatic visas issued to Nigerian citizens will now be single-entry and valid for only three months. It says this is part of a global reciprocity realignment, a sharp shift from previous visa terms, which often allowed for multiple entries over two years or more.

Larson said he didn’t realize he needed the ETA visa until the U.S. Open, and when he filled out the form he was denied. Grounds for refusal include an applicant who has been convicted of a criminal offense in the U.K. or overseas for which they served 12 months or more in prison.