Philadelphia’s Ben Revere scores the go-ahead run in the eighth inning. (Matt Slocum/Associated Press)

Kevin Frandsen reached his left arm above his head and stood on the toes of his right foot, his body stretched as possible. Keeping his spike on first base while catching Ian Desmond’s high throw — or not — would prove to be the difference between victory and defeat. The margin could not have been more narrow, cruel, or unavoidable.

“It’s basically your human nature,” Frandsen said. “How tall are you? How much of an arm length do you have on that?”

Frandsen has more or less willed himself into an eight-year big league career. In the pivotal moment of the Washington Nationals4-3 loss to the Philadelphia Phillies, Frandsen fell victim to a factor outside his control. He could not will himself to grow.

The Nationals suffered a second consecutive loss for the first time since Aug. 5, a testament to month-long excellence that allowed them to take control of the National League East. The loss at Citizens Bank Park turned in the eighth inning, when Phillies speedster Ben Revere reached on an impossibly close play at first base, stole second and scored on two flyballs yielded by Tyler Clippard.

Gio Gonzalez allowed three runs, all scoring on homers, in six innings. The Nationals scored twice in the seventh after Cole Hamels stifled them for six innings, and Asdrubal Cabrera tied it with a homer in the eighth. But the Nationals could not overcome something they could not change: Regular first baseman Adam LaRoche, on the bench with a sore back, is 6 feet 3, and Frandsen is 6 feet.

The Post Sports Live crew debates which Nationals pitcher should start a Game 1 in a playoff series. (Post Sports Live/The Washington Post)

“We got to live with it and I got to live with it,” Frandsen said. “Not being tall enough.”

In the eighth, just after Cabrera’s homer tied it at 3 and knocked out Hamels, Revere rolled a slow grounder to Desmond’s right. Desmond shuffled to field the ball, and he knew he needed to rush with Revere racing down the line.

The throw sailed, forcing Frandsen to stretch in both directions. First base umpire Gary Cedarstrom ruled Revere out. Phillies Manager Ryne Sandberg still possessed his challenge because he had won a close one in the first inning. He used it.

“We can see it one way,” Manager Matt Williams said. “Doesn’t mean they’re going to see it the same.”

The crew in New York ruled Revere safe. When Frandsen’s foot came off the bag, it would have taken WD-40 to wedge an index card between his foot and the bag.

“I was just sitting there trying to digest it, and I don’t think there was a whole lot else I could do,” Desmond said. “He hit the ball sharp to my backhand side. I was a little too close to backhand it. I don’t really have time to aim, I just have to get rid of it as quick as I could and make a good throw. But he’s safe — if he’s safe — by an inch at most.”

Revere promptly stole second off Clippard and catcher Wilson Ramos. Jimmy Rollins pushed him to third with a flyball to the warning track. Williams could have walked Carlos Ruiz, an excellent contact hitter, and put the double play in order. He did not, and Ruiz lofted a fly to right center. Clippard turned his back to the plate and watched, the damage already done. He knew Revere would trot home from third base, unchallenged, with the go-ahead run.

“Pretty close both ways,” Williams said. “They deemed he was off, then they stole second, got him over and got him in. They executed.”

Gonzalez pitched well enough for his first win since July 5, allowing three runs on six hits and a walk in six innings. He yielded a two-run homer to Freddy Galvis on a neck-high fastball in the fourth and another when Darin Ruf crushed a fastball down the chute over the fence in the fifth.

“It’s progress,” Gonzalez said. “I knew it was going to be a tough game from the beginning, Cole Hamels has been pitching great. I was going to try to match him up as much as possible. But other than, fastball was still live, curveball, change-up. You leave a ball up, they’re going to hit it.”

Hamels steamrolled the Nationals for the night’s first six innings. He allowed them three hits, all singles, and no walks while using only 59 pitches. He carried a 3-0 lead into the seventh, and it appeared he had been given two more runs than he needed.

Anthony Rendon changed that when he scalded a single up the middle. With one out, Ian Desmond smashed a single off third baseman Andres Blanco’s glove. Scott Hairston, starting against Hamels for the fourth time this season because of his destructive history against him, drew a walk to load the bases.

Wilson Ramos roped Hamels’s first-pitch fastball to right field for an RBI single. Next came Frandsen. He poked an opposite-field single to right, his 10th hit in 16 at-bats, scoring Desmond and slashing the deficit to a lone run.

“It wasn’t over 3-0. We know that,” Frandsen said. “We continue to grind. We continue to fight for each other. Not for anything else. Just get the next guy up and hopefully that guy will come through and nothing is ever over.”

The Nationals ran aground when pinch hitter Danny Espinosa smoked a line drive – “a bullet,” Williams said – right at shortstop Jimmy Rollins. Espinosa could not have hit the ball harder, but it only stalled a rally. It was that kind of night for the Nationals.

“Nothing you can do,” Cabrera said