Yu Darvish allowed three runs over seven innings, pitching the San Diego Padres to a 5-3 win over the Arizona Diamondbacks on Friday and collecting his eighth win of the season. Darvish (8-4) surrendered five hits and two walks while striking out nine for the Padres at Petco Park. After opening the game with back-to-back strikeouts, Darvish surrendered Ketel Marte’s eighth home run. With a 5-1 fourth-inning lead, Darvish allowed his second homer, Christian Walker’s 22nd of the season, with a man on. The Padres got Darvish the lead in the second, starting with a two-run double by his catcher, A…