SAN FRANCISCO — The Giants needed to generate some offense in Game 4 of the NLDS, with champagne on ice and a 2-1 lead in the series. Despite that advantage, the Giants had only scored three runs in their past 27 innings. They were stifled by Washington Nationals starter Doug Fister in Game 3 and were looking to do better against Game 4 starter Gio Gonzalez. The Giants did, jumping to a 2-0 lead in the second inning — but Gonzalez and the Nats sure gave them a hand. After Brandon Crawford singled with one out in the second, this sloppy turn of events followed and put the Nats in an early hole: • Juan Perez grounded back to Gonzalez, but the ball ricocheted away from him. The error put runners at first and second with one out. • Giants pitcher Ryan Vogelsong, looking to advance the runners, laid down a nice bunt. It rolled toward third base, but neither Anthony Rendon nor Gonzalez picked it up. The sac bunt turned into a bunt single and filled the bases. • A rattled Gonzalez then walked Giants leadoff man Gregor Blanco on four pitches, bringing home the first run of the game. The Giants scored another run when Joe Panik grounded to first base and Perez...