Mills competed for the men's 4 × 400 m relay at the 2008 Summer Olympics in Beijing, along with his teammates Ato Modibo, Jovon Toppin, and Stann Waithe. He ran on the third leg of the second heat, with an individual-split time of 46.60 seconds. Mills and his team finished the relay in fifth place for a seasonal best time of 3:04.12, failing to advance into the final.