HARTFORD, WI - JUNE 13: Jimmy Walker of the United States warms up on the practice green during a practice round prior to the 2017 U.S. Open at Erin Hills on June 13, 2017 in Hartford, Wisconsin. (Photo by Gregory Shamus/Getty Images)
HARTFORD, WI - JUNE 13: Jimmy Walker of the United States warms up on the practice green during a practice round prior to the 2017 U.S. Open at Erin Hills on June 13, 2017 in Hartford, Wisconsin. (Photo by Gregory Shamus/Getty Images)