As the bullpen door swung open in the sixth inning Tuesday night, a wave of hope rippled through the stands at Citi Field.

The Mets were at it again, falling into a hole, before showing signs of bashing their way out of it. The responsibility to keep the good vibes flowing fell to Bobby Parnell.

Instead, his disastrous outing in a 14-8 loss to the Phillies underscored the consequences of questionable decisions in the heat of a pennant race.

Parnell, fresh off the disabled list, walked the first two batters he faced, then threw away a sacrifice bunt back to the mound.

His implosion triggered an eight-run sixth, with the calamity unfolding after the Mets rallied to cut a 6-0 deficit to 6-4.

"It was the bottom of the order," Collins said of a decision that left him open to scrutiny. "And I thought if we get him back out there after what he's been through, I thought it might be a lift for him."

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Instead, Parnell walked off the field to perhaps the loudest boos at Citi Field this season.

"Things aren't going my way right now," said Parnell, who showed life on his fastball, but no command of it. "It's not where I want to be."

As the first-place Mets attempt to hold off the Nationals, who are 61/2 games back, they must sort through a bullpen that appeared to be a strength at the start of the season.

While Tyler Clippard and Jeurys Familia have given the Mets a lockdown presence, the arms behind them have faltered.

They represent the Mets' biggest vulnerability. They were left exposed after Jonathon Niese was thrashed for six runs in five innings, raising his ERA to 9.92 in his last three outings.

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Later in the sixth, lefty Eric O'Flaherty (two runs) and righty Carlos Torres (three runs) let the inning get out of hand.

The Mets acquired O'Flaherty just after the trading deadline hoping he could be an effective lefty specialist. Instead, after the only batter he faced walked and scored, his ERA with the Mets jumped to 14.14.

Meanwhile, three arms who might factor into the postseason mix did not see action until later in the game. Addison Reed, acquired from the Diamondbacks last weekend, tossed a scoreless inning.

Erik Goeddel, appearing for the first time since June 11 because of an elbow injury, lowered his ERA to 1.88 with a scoreless ninth. Lefty Sean Gilmartin (2.20 ERA) struck out the side in his only inning.

Any of the three would have been available for Collins with the lead within reach.

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In the Mets' four-run fifth, Kelly Johnson delivered a pinch-hit RBI single. Curtis Granderson grounded out to knock in another run.

Yoenis Cespedes broke out of an 0-for-15 funk with a missile over the leftfield stands. His two-run shot -- his career-best 28th homer -- cut the deficit to 6-4.

But just as quickly as the Mets roared back, they were careening toward their first loss to the Phillies in 10 games.

Parnell has not been the same since being afflicted by the double-whammy of a herniated disc in his neck and Tommy John surgery, wrecking his last two seasons.

His latest episode involved landing on the disabled list, his choice after the Mets offered him the undesirable alternatives of being designated for assignment or accepting a minor-league demotion.

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He was charged with three runs (two earned) as his ERA climbed to 6.52. Said Parnell: "It's been a long two years."