With Pablo Sandoval back, the Giants finally have the 3-4-5-6 portion of their lineup set up the way management envisioned when it dealt for Hunter Pence. When Melky Cabrera, Buster Posey, Pablo Sandoval and Pence started together for the first time Tuesday night, the middle of the lineup looked as formidable as it has in years. If future foes were watching the Giants finally beat the Nationals, 6-1, they learned another lesson, too: They better not sleep on the No. 7 hitter.