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.

His job was simple. After watching the Mets cut their six-run deficit against the Phillies to two, it was on the righthander to hold the line.

Instead, Parnell's disastrous outing in a 14-8 loss displayed the Mets' biggest vulnerability.

While Tyler Clippard and Jeurys Familia have given the Mets a steady lockdown presence late in games, the rest of the Mets bullpen has faltered.

That weakness emerged again in the sixth, when fans booed Parnell off the field, shortly after he ignited what became a full-scale bullpen meltdown.

"He just didn't throw any strikes," said Terry Collins, who turned the reins over to a fresh-off-the-DL Parnell despite a bullpen filled with other options.

The brutal sixth came after the Mets rallied from 6-0 down, the result of the Phillies blasting Jonathon Niese (8-10) for six runs in five innings.

In the Mets' four-run fifth, Kelly Johnson had 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 to left. His two-run shot -- his career-best 28th homer -- cut the Phillies' lead to 6-4.

Just as quickly as the Mets roared back, they found themselves in the abyss. The Phillies pounded three relievers for eight runs in the sixth, an onslaught that began with Parnell.

The former closer has not been the same since being afflicted by the double whammy of a herniated disc in his neck and Tommy John surgery, which wrecked 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.

Said Parnell: "It's been a long two years."

Earlier in the day, Collins said newly acquired reliever Addison Reed needed game action. He said the same about lefty Sean Gilmartin, who has been effective in long relief.

Erik Goeddel, a September call-up who the organization believes might bid for a bullpen role, also was available.

Instead, with the bottom of the Phillies' order due up, Collins turned to Parnell. He promptly walked the first two hitters he faced. Then, he threw away Freddy Galvis' sacrifice bunt attempt. Parnell (6.52 ERA) agonized over the mistake, remaining doubled over as the ball rattled around the rail behind first base.

Later, he watched from the dugout as lefty Eric O'Flaherty (two runs) and righty Carlos Torres (three runs) struggled to end the inning.

The Mets acquired O'Flaherty just after the July 31 trade deadline, hoping he could be an effective lefty specialist. Instead, after the only batter he faced walked and later scored, O'Flaherty's ERA with the Mets jumped to 14.14.

Meanwhile, three arms that the Mets might actually use in the postseason didn't see action until later in the game. Reed, Gilmartin and Goeddel tossed scoreless innings.

Now, as the Mets attempt to hold off the Nationals, they must also sort out a bullpen that appeared to be a strength at the start of the season.