Third baseman Ryan Zimmerman’s pregame mood didn’t improve after striking out with the bases loaded in the eighth inning Tuesday as part of an 0-for-4, two strikeout performance. (Matt Slocum/Associcated Press)

The Washington Nationals at least forced Cole Hamels to exercise the full extent of his powers Tuesday night. In the eighth inning of their 4-2 loss to the Philadelphia Phillies, they loaded the bases with one out. The opposing manager considered using his bullpen, then trudged back to the dugout without having taken the ball. Jayson Werth, perhaps Citizens Bank Park’s leading villain, walked to the plate with two outs.

The theater was good, but ultimately the wrong half of the Nationals’ bipolar offense surfaced. Werth’s flyball would die short of the warning track, the Nationals’ best threat ended with another zero on the scoreboard and the gap between them and the Atlanta Braves in the National League East expanded back to six games.

A last-gasp rally in the ninth resulted only in a cosmetic run as the Nationals failed to support rookie right-hander Taylor Jordan with their bats or gloves. The Nationals managed seven hits, most prominently Werth’s solo home run in the second. Slipshod defense contributed to half the Phillies’ runs as Jordan hung tough, allowing three earned runs in 52 / 3 innings on eight hits, just not with enough skill to outdo Hamels.

In their past 10 games, the Nationals have scored at least eight runs five times. They have also scored two or fewer runs four times over the same span. With the return of Bryce Harper and Wilson Ramos, the Nationals regained the ability to score in droves. But they have also not shaken their penchant for filling thimbles halfway. The engine purrs or the battery shorts.

“I can’t explain it,” first baseman Adam LaRoche said. “It’s one of those things you try to go out and get 15 hits before you get the first one. And nothing good happens.”

The Post Sports Live crew discusses Bryce Harper’s “play me or trade me” text to Davey Johnson and whether the outfielder has too much control over when he plays. (Post Sports Live)

Hamels is one of the most accomplished pitchers of his generation, but for the Nationals, what mattered most, perhaps, is that he happens to throw with his left arm. The Nationals are hitting .215 against left-handed pitchers, dead last among all 30 major league teams. The past two nights, the Nationals have scored one run in 16 innings off lefty starters John Lannan and Hamels.

They tried to remedy their weakness by trading for veteran outfielder Scott Hairston, a right-handed hitter. Manager Davey Johnson batted Hairston leadoff against Hamels, and he went 2 for 5 in his Washington debut, flying out to right as the potential tying run for the final out.

The Nationals tried everything against Hamels. In the first inning, shortstop Ian Desmond batted with a patch of hair covering his chin and grounded into a 4-6-3 double play. In the third, he stepped to the plate clean-shaven. “That goatee was weighing me down,” Desmond said. With a hairless chin, Desmond popped to right.

The Nationals entered the eighth inning trailing by three, but finally showed some fight against Hamels. Harper drew a hard-earned walk to load the bases with one out. Ryan Zimmerman stood on deck. Phillies Manager Charlie Manuel ambled to the mound, but he left without the ball. Hamels’s pitch count stood at an even 100.

Zimmerman took strike one, a fastball at the knees over the outside corner, and turned around to glare at home plate umpire Vic Carapazza. “Borderline, at best,” Zimmerman said afterward. Zimmerman fouled the next pitch back to the net. Hamels fired a high, 92-mph fastball with his first chance to finish Zimmerman off, and Zimmerman swung through it.

The crowd was already frenzied as Werth came to the plate. Werth took a fastball for strike one, then a curve at the top of the strike zone for strike two. He fouled away one pitch. He laid off a fastball outside, spit on a change-up in the dirt and took a fastball outside. Hamels would not give in, and neither would Werth.

“He was playing the guessing game,” Hamels said. “He got me in that first at-bat. He had made me more aware, to be more careful with him. He’s been here. He’s seen me a ton. I’ve seen him a ton. It’s a serious guessing game and chess match we have between us. He’s a great hitter. You have to make great pitches to him. And even when you do, sometimes he’ll have hits.”

Hamels finally fed Werth a 3-2 fastball over the plate. Werth drilled it to right-center field, getting under it just enough. Center fielder Ben Revere chased it down a step in front of the warning track. The confrontation had been as evenly contested as pitcher-batter can be.

“Big-time battle,” Manuel said. “That’s what baseball is all about.”

The Phillies had taken control in the sixth. Revere and Jimmy Rollins poked consecutive singles to lead off the inning. All night, Jordan had squirmed out of jams with groundballs, inducing three double plays in the first five innings. Jordan threw Chase Utley another sinker, and he chopped it to the right side of the infield, another potential twin killing.

“That was perfect,” Jordan said. “What I wanted to do.”

LaRoche fielded the ball on a high hop and whipped a sidearm throw to Desmond at second. At worst, it seemed, the Nationals would still be tied at 1 with two runners on base and one out. And then Rollins veered into the line of LaRoche’s low throw, and it deflected off Rollins and rolled into shallow left field.

“That’s unbelievable baserunning,” Desmond said. “That’s really good wherewithal. There’s probably things that we could do differently, but at the same time, he did a very good job. That’s something that you don’t see from very many other players.”

Revere trotted home, Rollins scooted to third and Utley stood on first base. The Nationals trailed, 2-1, and the Phillies had runners on the corners with no outs.

The bullpen had remained dormant, and so Johnson had left himself no choice but to let Jordan pitch his way out of another jam. Craig Stammen began warming as pitching coach Steve McCatty trundled to the mound.

Jordan got cleanup hitter Domonic Brown to pop out to short, but Michael Young crunched a two-run double to right-center field. This time, Johnson walked to the mound and asked for the ball.

The Nationals had plenty of time left to score. Their offense had showed enough in recent games to provide hope. But it had also shown enough impotence to make another string of zeroes a distinct possibility.