WASHINGTON, DC - JULY 29: Bjorn Fratangelo of the United States prepares for a shot from Ivo Karlovic of Croatia during Day 1 of the Citi Open at Rock Creek Tennis Center on July 29, 2019 in Washington, DC. (Photo by Mitchell Layton/Getty Images)
WASHINGTON, DC - JULY 29: Bjorn Fratangelo of the United States prepares for a shot from Ivo Karlovic of Croatia during Day 1 of the Citi Open at Rock Creek Tennis Center on July 29, 2019 in Washington, DC. (Photo by Mitchell Layton/Getty Images)