Peavy carried a two-hit shutout into the seventh inning in his first start since April 17, but his lone big mistake, a two-run Clint Robinson homer, sent the Giants to a 2-1 loss, their fourth in four games on this journey. Buster Posey hit Gio Gonzalez's first pitch of the seventh inning into the seats just left of straightaway center for the game's first run and his fifth homer in the past two weeks. Peavy walked him for the third time, on a close 3-2 pitch, before Robinson lined his fourth hoemr of the year into the right-field seats to give the Nationals a 2-1 lead. The Giants enjoyed a leadoff single in each of the first three innings (Pagan, Andrew Susac, Gregor Blanco) but did not advance a runner to third. Pagan had two hits, including a one-out single in the sixth, but committed a blunder that ended the inning. [...] baseman Danny Espinosa fielded it and threw to second to attempt a force. A flurry of roster moves continued Friday when the Giants again cut Travis Ishikawa, designating the 2014 playoff hero for assignment, and replaced him with long-time minor-league outfielder Ryan Lollis, a move that manager Bruce Bochy said "totally" stemmed from the rash of outfield injuries. Once again, Ishikawa's career with the Giants might be over, this time after six 2015 plate appearances. The Giants also optioned right-handed reliever Mike Broadway to Triple-A Sacramento to give Bochy a second left-hander in the bullpen, Osich, who is healthy after what seemed like perennial arm problems in the minors and was thriving at Double-A Richmond, Va.