McDowell and Dunne out early at US Open; Johnson relaxed ahead of title defence

Play may be delayed over the next four days as bad weather is forecast.

Paul Dunne and Graeme McDowell are among the first out at the US Open in Wisconsin today.

Dunne starts after noon while former winner McDowell begins just after 1pm. Shane Lowry and Rory McIlroy start their rounds this evening.