Students, adults, and even a food truck lined almost all the fencing around the baseball field at Holy Spirit High School Tuesday afternoon, a much different atmosphere than most mid-April varsity games in South Jersey. More unusual was the 50 or so scouts seated in metal bleachers directly behind the backstop, most of them armed with black radar guns.

The curiosity seekers were all there to witness the same thing: Chase Petty’s fastball or, to be more precise, his 100-mph fastball.

The Mainland High School senior did not disappoint. He topped out at 102 a couple times in the early innings before settling in at 95 to 97 mph while mixing in a nasty breaking ball and a nifty changeup. When his day was done, he had pitched a complete-game one-hitter and struck out 13 of the 25 batters he faced, including the final hitter in the bottom of the seventh with a fastball that lit up the arsenal of radar guns at 98.

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Ten minutes after he had led Mainland to a 5-2 opening-day win against a Holy Spirit squad that is ranked No. 2 in the state, Petty was still experiencing the natural high of his first high school baseball game since his sophomore season.

“I feel great,” he told reporters. “I could keep going. The adrenaline was just rushing through my body the entire time. It was just great. This was by far the best experience I’ve had in the past few years.”

What Petty, who turned 18 earlier this month, did on the field Tuesday was impressive. In addition to his 89-pitch complete game, he also contributed a couple of hits, walked once and scored two runs.

“He’s arguably our best player when he isn’t pitching, too,” Mainland coach Billy Kern said. “He runs well, he does everything well and he does everything with a smile and he competes.”

Baseball America ranked Petty the second-most athletic high school pitcher in this year’s draft, which is scheduled for July 11-13 in Denver. He is also ranked as having the best fastball and best fastball movement among prep pitchers.

Home runs by teammates Brody Levin and Cole Campbell off Holy Spirit’s West Virginia-bound David Hagaman in the top of the first inning gave Petty a 3-0 lead Tuesday before he went to the mound. Four batters into his much anticipated outing, he had given two of those runs back.

Rutgers-bound Trevor Cohen lifted a one-out triple into left-center field to account for Holy Spirit’s first run and what would be his team’s only hit. Cohen scored on a groundout to second to make it 3-2.

The rest of the sunny wind-swept afternoon belonged to Petty. He finished the first with the first of his 13 strikeouts and allowed just three baserunners – two walks to Cohen and a hit batter – the remainder of the game.

As the New Jersey high school season begins, Petty is projected as a late first-round pick. Baseball America’s most recent mock draft had him going to the World Series champion Los Angeles Dodgers with the 29th pick. The Phillies select 13th overall. Petty is a New York Yankees fan even though he was raised in Mike Trout’s hometown of Millville before moving to the Mainland sending district of Somers Point before his freshman year.

“My parents were Yankees fans and I just grew up with it in the family,” Petty said.

The Yankees have the 20th pick.

For now, the draft is in the back of Petty’s mind. He was deprived of his junior season by the pandemic and limited to a handful of games as a sophomore by a knee injury. He also has a scholarship offer to the University of Florida in pocket.

“Every kid in a position like me sees (the draft) as a possible future,” Petty said. “But the biggest thing for me is focusing on the now. I still have this whole season to perform and compete. That’s really just my main focus right now and as of right now I’m 100 percent going to Florida. As time goes on, we’ll see what happens.”

Major-league scouts are sure to flock to the remainder of Petty’s games this season, but they will be looking for more than just velocity.

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“As far as pitching goes, velocity is a wonderful thing, but you really want to see someone who can throw to both sides of the plate and command the fastball,” said a big-league scout who plans to attend Petty’s next outing Wednesday at Millville. “I’ve seen guys in the big leagues who are unable to do that and they’ve struggled even though they can throw 100. Velocity excites people, but you still have to get people out.”

Recent draft history also tells us that there’s a lot more to pitching than triple-digit radar readings. The Cincinnati Reds took Hunter Greene second overall in 2017 after he touched 102 mph during his senior season at Notre Dame High School in Southern California, but after 21 starts at the lower level of the minor leagues, he has a 4.95 ERA. Tommy John surgery and the COVID-19 pandemic have also kept him off the mound since 2018.

In 2016, the Colorado Rockies took Riley Pint fourth overall after he had lit up the radar gun at 102 for his high school team in Overland Park, Kansas. He has a 5.71 ERA in 58 minor-league appearances, none of which have come above low-A ball. He has also had shoulder and forearm injuries.

“There’s always a concern that physically guys who throw that hard in high school are not catching up to what their arms are doing,” the scout said. “There’s a concern they may break down at some point and there are concerns about what they’ve done to get to that point.”

Those concerns will not stop throngs of students, parents and scouts from flocking to the Chase Petty Show this spring at fields across South Jersey and the eponymous star of the show intends to enjoy every minute of it.

“Yes, absolutely,” Petty said. “I’ve been waiting to get out here with these guys a long time. I consider them my brothers. I’ve been together with most of them for four years and we’ve built a great relationship together. It was great to be back out there with them.”

That answer was almost as impressive as his 102-mph fastball.