The New Zealand runner Nick Willis has warmed up for the World Atheltics Championships with victory in a mile race at his base in Michigan.
Willis ran his tenth fastest mile in winning the Running Institute Mile in three minutes and 56.57 seconds.
Willis was aiming for the Michigan State record of three minutes and 55.87 seconds.
His best mile is three minutes and 50.66 seconds, set in 2008.
The US based Hutt Valley runner now heads to Moscow where he will have his first race in the heats of the 1500 metres next Wednesday.