Nawn, an assistant bowling coach and assistant principal at St. Joseph's Prep, ended up completing 15 games as an amateur in last year's USBC Masters on the PBA Tour.
Minutes later, his cellphone rang.
His wife, Mary, had waited till he was finished to call. Their son Joseph, then 15 and struggling with a central-nervous-system disorder, had lost the ability to walk and was taken to Children's Hospital of Philadelphia. Just like that, the euphoria faded.
His second of five children doing better, Joe Nawn struggled recently over whether to return to the tournament in North Brunswick, N.J., and make the financial commitment that the Masters requires.
Then Joseph became a factor again.
"Joseph - bless his heart, he has the strength of 10 people - said, 'Dad, last year I was in the hospital and couldn't see this. I want to see this. You've got to go,' " Nawn recalled.
So, Nawn will go. He will take a vacation from St. Joseph's Prep next week to fulfill a dream for the second time. He will be among 148 amateurs, he said, in a field that includes 320 pros.
"Part of the reason I'm going," Nawn said, "is I want to bowl for him. I would love for my son to see me, and I'd love to do well for him. He is really proud of his dad, and it's very humbling."
The USBC Masters is an open tournament and one of the PBA's annual majors. Nawn, a 46-year-old lefthander, and any other amateurs may compete in an open PBA tournament if they have averaged at least 210 in league play over the last two years.
Nawn is averaging 228 this year, and he has thrown 20 perfect games in his career, all since 1998.
His average would place him seventh on the PBA Tour this year. But there's a huge difference between 228 in regular league play and 228 on the tour, because of the circuit's different oil patterns and immense pressure.
"What I tell people is if you take your average in league and subtract 30 pins, that'll tell you where you're at. It's that difficult," he said of the tour.
The tournament will begin Sunday with five games of unofficial practice. Monday, there will be five games of official practice. Nawn will bowl five qualification games each of the next three days before the field is cut to 64.
Nawn, who lives in Upper Darby and considers Facenda-Whitaker Lanes in East Norriton his bowling home, praised the support he has received and said he will have two people in the stands cheering for him each day in North Brunswick.
One of them, one day, will be his son Joseph.
"It's going to be awesome, really," Joseph Nawn said. "I like watching him bowl, because he's really good sometimes."
Joseph Nawn, on medical leave from St. Joseph's Prep, suffers not only from the central-nervous-system disorder but also from autoimmune hepatitis, a disease in which the body's immune system attacks the liver. He takes medications for both conditions.
"He is in pain most days," Joe Nawn said. "Never complains. Never complains."
The USBC Masters is a costly venture for Nawn. There's a $500 entry fee, he said, and he has spent about $750 on equipment. "And then hotel, gas, food, it's about a $1,500 weekend," Nawn added. Cash prizes, he said, will be awarded to the top 100 finishers.
Nawn placed 250th out of 468 last year, averaging 195 for his 15 games. He wants to average 210 this time.
"I'd love to make the cut. I really would," he said, "but I've got some more work to do for that."
Nawn has certainly put in the work since he was cut from the Monsignor Bonner team in his first three years there. He tried a fourth time, but the coach didn't accept senior walk-ons.
He had started bowling when he was around 5 with his grandmother Jeanette Locilento. He said he and Locilento, who died 18 years ago, were "inseparable."
"I would always say, 'Wouldn't it be great someday if I could ever bowl on tour?' " Nawn recalled. "Now, grandmothers being grandmothers, she said, 'Of course, Joey.' "
Nawn didn't start with competitive leagues until he was 20. He has averaged in the 220s regularly for about a decade, he said, with a highest season average of 236.
These days, Nawn bowls in three leagues, two at Wynnewood Lanes and one at Facenda-Whitaker, and estimates he averages about 12 games a week. To get ready for the big time, he has ratcheted that up, rolling 30-35 per week.
And to help him, a few days ago, the owner of Facenda-Whitaker prepared two lanes in an oil pattern similar to what Nawn will face in North Brunswick.
The rest will be up to Nawn, on one of bowling's biggest stages.
He'll have his grandmother's old pink towel in one of his bowling bags.
He'll have his son Joseph in the stands one day.
He'll have pros to his left and pros to his right.
It'll be a dream come true, once more.
"Imagine, for a week, you get to honestly pull on an Eagles jersey and be a Philadelphia Eagle," Nawn said. "You wouldn't trade that for gold.
"In [a few] days, I get to pull on a jersey and bowl with the pros."