But the crowd's roar told Pence what he had missed: Washington center fielder Denard Span raced into the gap and caught the ball before plunging to the grass and sliding to the warning track, carried by his momentum. An instant earlier, that momentum belonged to the Giants, who absorbed a 6-5 loss.
This defeat differed from most of the Giants' recent setbacks. They sustained an inspired comeback that appeared destined to succeed. Instead, Span joined the gallery of thieves that includes San Diego's Will Venable and the Dodgers' Matt Kemp, who made game-ending grabs to foil San Francisco rallies earlier this year.
When grown men play for money -- that's what professional sports is, right? -- there's no such thing as a good loss. But given the Giants' sinking fortunes, this was about as close to a good loss as can be imagined.
"It was really spectacular to even be in that situation," Pence said. "We fought hard. ... That's what this game's about."
Washington forced the Giants to scramble by surging ahead, 6-1, with a five-run fourth inning off Tim Lincecum. The uprising featured two infield hits, including Jayson Werth's swinging bunt toward third base, and Kurt Suzuki's run-scoring bloop single. Lincecum's only true lapse was a 2-2 fastball that rookie Anthony Rendon belted for a two-run, bases-loaded double.
"That's horrible luck," Giants manager Bruce Bochy said, referring to Lincecum's performance. "He had good stuff."
Washington's outburst prompted the Giants' seventh loss in a row at Nationals Park, dating back to 2011. But the reigning World Series champions showed some of their pluck before being counted out.
The Nationals needed three pitchers to weather the eighth, when the Giants scored three runs. With one out, Belt clobbered his 13th homer of the season. The drive was made impressive by its distance -- it landed with a thud on an unoccupied seat in the second deck in right field -- and by the fact that the left-handed-swinging Belt victimized a left-handed pitcher, Ian Krol.
"That certainly helped bring the guys back to life," Bochy said.
In came Ryan Mattheus, who surrendered Posey's single, Pence's infield hit and Pablo Sandoval's two-run double, a line drive to the right-center-field gap. It was Sandoval's third hit, exceeding his total for the previous seven games (2-for-23).
"We've got to get Pablo going," Bochy said before the game. "He's such a big part of this offense. He's probably going through one of the toughest skids he's gone through."
Sandoval acknowledged after the game that he has been late on fastballs he typically crushes.
"I've been doing everything I can to get back," he said.
Tyler Clippard struck out Roger Kieschnick and Gregor Blanco to end the eighth, but the Giants weren't finished. Pinch-hitter Hector Sanchez christened the ninth by singling off Nationals closer Rafael Soriano, who retired the next two hitters. Then Belt singled home pinch-runner Andres Torres. Posey also singled, sending Pence to the plate for the dramatic conclusion.
Belt recognized Pence's solid contact immediately.
"Being on second base, I could see he stayed on the ball really well and put a good swing on the ball," Belt said.
Span was playing Pence in right-center field, which made his chase more challenging.
"I thought it was in the gap and it was a long, long way from him," said Pence, who hadn't seen a television replay of Span's catch. "He apparently made a spectacular play. I was shocked."
Said Span, "Off the bat, I actually took a false step, kind of stepped in a little bit and I just broke for the ball and put my head down two or three steps, and I was able to come up with the ball."
Afterward, Bochy walked through the clubhouse and praised players for their effort. He ducked into the training room to comfort the physically sore Giants, then approached Lincecum and shook his hand.
"They fought so hard," Bochy said. "It's a shame they couldn't get a break."
Or, as Pence said, "If it was Candyland every year and you won the World Series every year, who would want to watch?"