With no outs in the frame, A's right-hander Jarrod Parker threw a pitch that grazed the back of Daniel Nava before hitting Bucknor. He was examined by A's trainer Nick Paparesta for several minutes before departing.
Jane Lee is a reporter for MLB.com. Read her blog, Major Lee-ague, and follow her on Twitter @JaneMLB. This story was not subject to the approval of Major League Baseball or its clubs.