Knaggs has been the AppleSox head coach since 2001. He has led the AppleSox to five league championships, winning the Pacific International League Championship in 2003 and the West Coast League Championship in 2005, 2006, 2009, and 2010. He is a three-time recipient of the WCL's Coach of the Year Award. He played collegiately at UC Irvine and was an assistant coach at Gonzaga University for seven years. He also spent one season as an assistant coach for the Chatham A's of the Cape Cod League. He has served as Wenatchee High School’s head baseball coach since 1991 and was instrumental in bringing back American Legion baseball to the Wenatchee Valley.