By his own admission, Jeff Singer has taken an unlikely path to his improbable status as one of the more intriguing prospects in the Phillies minor-league system.

"The alternate route," Singer calls it.

Rowland George, the Phillies scout who signed Singer, regards the story of the left-hander pitcher from Holy Cross Academy in Delran, N.J., and Rutgers Camden University as something out of a "fairy tale."

Singer, who was signed by the Phillies in October 2015 after a stint with the now-defunct Camden Riversharks of the independent Atlantic League, made enough of an impression in his first season in the minor-league system to earn an invitation to the prestigious Arizona Fall League.

That's highly unusual for an undrafted free agent and especially so since Singer played for a NCAA Division III college program and was pitching in the Rancocas Valley men's league just 15 months ago.

"This is a big step for Jeff," said Joe Jordan, the Phillies director of player development. "He really, really impressed us. His stuff got better all year, and his ability to use his stuff improved all year.

"We challenged him . . . and he handled it."

The Arizona Fall League is a showcase for many of the top prospects in baseball. Major-league teams can send six or seven minor-league players to the six-team league, which begins Tuesday and runs for six weeks.

"I was a little surprised," to be invited, Singer said. "It's a great opportunity."

Singer's rapid rise has coincided with a sharp increase in the velocity of his fastball.

The 6-foot, 200-pound Singer was throwing around 85 mph as a senior at Holy Cross Academy in 2011.

In appearances with three Phillies' minor-league teams this past summer, Singer's fastball was sitting around 95 mph and touched 99 mph on several occasions, according to George.

"I went to see him at Lakewood, and I'm looking at the scoreboard, and it's showing 99 mph," said Jim Ulrich, Singer's agent. "You can count the lefties on one hand who can throw 99-plus in a game at any level."

In two seasons at Gloucester County College, one at Monmouth University and one at Rutgers Camden, Singer improved his fastball to the 90-mph-range. But he wasn't drafted after his final season for Rutgers Camden in the spring of 2015.

"He threw a no-hitter mid-season, and I think he was overthrowing a little after that," Rutgers Camden coach Dennis Barth said. "He got back to normal in the summer and has been dealing every since."

The 23-year-old Singer traces his improvement in velocity to a couple "tweaks" in his mechanics by Phillies' instructors as well as the fact he "matured late" in terms of his physical strength.

"They got me using my legs more, slowing down and staying behind the ball," Singer said of Phillies' pitching instructors.

Singer was born in Philadelphia and lived there for three years before moving to Cinnaminson in Burlington County. His family is filled with life-long Phillies fans.

"Just an incredibly hard-working, well-grounded kid from a great family of die-hard Phillies' fans," Holy Cross coach Steve Paolini said of Singer.

Singer said he pitched with a "chip on my shoulder" early last summer to prove he belonged with the team's other prospects.

Now he has an opportunity to show he can compete with many of the sport's top prospects.

"It's another opportunity for me to get better," Singer said. "I go in with the same mindset I've had all along, to have fun and compete."

panastasia@phillynews.com

@PhilAnastasia

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