NEW YORK -- As a fledgling pitcher for Charleston Southern University, Bobby Parnell was not particularly good. His velocity did gradually increase throughout his three-year career there, after he converted to mound work at age 17. But in his final season, Parnell walked nearly six batters per nine innings en route to an 8.86 ERA.
Later, as he rose through the ranks of New York's farm system, Parnell did so more on the promise of his boundless potential than the merits of any tangible improvement. His sky-high ERAs as a starting pitcher did not deter the Mets, who had drafted him in the ninth round in 2005.
Mesmerized by Parnell's rocket-fueled fastball -- that was really the only tool he possessed at the time -- the Mets almost stubbornly continued bumping him up the organizational ladder. They understood that if he ever figured out how to harness his natural gifts, Parnell would succeed.
"Some guys never find it," pitching coach Dan Warthen said. "He's found it. Hopefully he'll keep it."
Parnell completed the process of "finding it" last year, gaining better control of his fastball to post a 2.49 ERA over 68 1/3 innings. But he did so in relative obscurity. Even when filling in at closer for the oft-injured Frank Francisco, Parnell rarely did or said anything particularly noteworthy.
In that sense, another transformation has taken place this season, perhaps best defined by what happened Tuesday in Miami. Because Parnell had thrown three innings over the previous two days, including two in Monday's loss to the Marlins, manager Terry Collins passed over Parnell in the ninth inning with the game on the line.
Subbing for Parnell, middle reliever Brandon Lyon coughed up the lead and the Mets lost the game. And Parnell was visibly heated, fuming in the clubhouse afterward.
Collins' justification, which he relayed to the closer at the time, was that he wanted to protect the muscles and ligaments in Parnell's right arm. But the most noteworthy aspect of the situation was the simple fact that Parnell made it an issue.
"I still would have been upset if I didn't pitch in a tight game [in years past]," Parnell said. "It's just a little more prominent -- in the spotlight more -- because I am the closer."
Not surprisingly, Collins and his staff consider that a good thing. Third baseman David Wright, one of the only current Mets there to witness Parnell's debut in 2008, cited it as the latest evidence that New York's new closer is "taking control" of a bullpen staffed almost entirely by pitchers several years his elder.
"He's just asserting himself as the leader of the bullpen and the guy you want in the ninth inning," Wright said. "No question, there's a different mindset for him."
Parnell's late-game mentality grew pronounced in the early days of Spring Training, when Francisco suffered a setback in his rehab from right elbow surgery. Acting quickly in naming Parnell the closer, Collins went as far as to use him in the ninth inning of exhibition games -- an unorthodox bit of managing, considering most regulars are long gone from the games by that time -- so he could acclimate to the role.
Parnell's attitude changed with the assignment.
"When it comes the ninth inning and it's a save situation or a close ballgame, in my head, that's my inning," he said. "Every one of us down there can pitch in that inning. Every one of us is capable of doing that. But since Day 1 of Spring Training, in my head, I've thought, 'That's my inning.' I want to be out there."
It helps that despite multiple letdowns in past runs as the closer, Parnell has thrived over his first five full-time weeks on the job. Though he does have two blown saves in five opportunities, one was directly due to a Ruben Tejada throwing error and the other was influenced heavily by a Collin Cowgill misplay in center field. Parnell's overall body of work has been nearly spotless, with 11 strikeouts, two walks and a 1.38 ERA in 13 appearances. The league is hitting .143 off him.
"It was just a matter of enough innings and enough time and enough experience," Warthen said. "He recognizes his delivery. He recognizes where his release points are, and he has worked hard on it."
The real change has come off the field, where Parnell no longer projects his former shy country-boy image. Though he maintains the same easygoing personality, Parnell has been more assertive in communicating with his manager, his teammates and the media. He may never mimic Billy Wagner's outsized character or Francisco Rodriguez's intensity, but he seems to have gained a bit of an edge.
Closers need that.
"I want to be in the game in tight situations," Parnell said. "I want to pitch. I'm probably a little bit more in the spotlight now that I'm closing, but it is what it is. That's part of it."
Anthony DiComo is a reporter for MLB.com. Follow him on Twitter @AnthonyDicomo.