DAYTON, Ohio -- Hunter Greene knew it was the last pitch he was going to throw in his Dayton Dragons debut on a chilly Monday night at Fifth Third Field, so he wasn't holding back.
When Lake County left fielder Austen Wade swung through a slider to end the third inning, stranding two runners, the 18-year-old Sports Illustrated cover boy pumped his fist as he jogged off the mound.
Greene said he lives for situations like that. The Reds, at that moment, might have glimpsed their future.
"That's when you really become a pitcher, when you get into a jam and have to bear down," said Greene, who was drafted No. 2 overall by the Reds in last year's amateur draft. "That's when you really show that you know how to throw in certain counts and have all the pitches in your arsenal. Man, I love that."
Greene, who made a brief pro debut last year in Billings, pitched three innings on Monday, allowing two runs and five hits. He struck out eight and walked none over 53 pitches, 35 of which were strikes. He showed velocity, but wasn't overly reliant on his fastball.
"I was very impressed," Dayton manager Luis Bolivar said. "The slider's getting better and better. He got in the jam in the third inning. Never bothered him. He concentrated. Very nice by him. Kid has a high ceiling."
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Greene, who became the youngest American pitcher in Dayton Dragons history on Monday, fanned his first batter -- Lake County second baseman Jorma Rodriguez -- on four pitches including the first three at 100 mph and an 86-mph slider to finish him off.
A two-run double to left field by left-handed batting Wade wasn't hit particularly hard, but the Captains' batters did turn on a couple of Greene's fastballs for hard singles. Greene threw 20 pitches in the first, 14 for strikes.
He was more efficient in the second against the bottom third of the Lake County order, retiring the Captains in order with two strikeouts on just 15 pitches.
Second time through the Captains order, however, Greene ran into some trouble by allowing two singles with a wild pitch to put runners on first and third with no outs to begin the third. In his most impressive sequence in Monday's game, Greene needed 16 pitches to fan the final three batters, including Wade, to end the inning.
"It happens," Greene said of his third-inning struggles. "To be able to bounce back and show your maturity and show your competitiveness is what I was trying to do. I had a little more of a plan when I came back out that last inning, I looked at the pitching stuff a little bit and knew how I was going to approach the next couple hitters."
Although Greene's velocity raised eyebrows in the first inning, it was his off-speed pitches that resulted in the majority of his eight strikeouts. He did not walk a batter in the game, which the Dragons won 3-2.
"Everybody's sitting dead-red fastball," said Greene, who only threw a couple changeups. "To be able pick the right count to throw my secondary pitches. I wasn't looking at the radar gun. I was just out there pitching and competing like I normally do."
At a game-time temperature of 39 degrees, Monday might have been the coldest game Greene has ever pitched.
The California native said the weather didn't bother him. He had a heat pack in his back pocket, extra clothing, and there was a heater in the dugout. After a few pitches, it was just baseball.
"I was warm, and ready to go," he said. "It was different for sure, with where I am from."
The thing that stood out with Greene was his effortless delivery. Even as a teenager with a 6-foot, 4-inch frame, he doesn't coil up like Aroldis Chapman or exhibit any wasted movement. His movements stay refined and his lower body stays grounded.
Greene made just three starts at Rookie League Billings last season before moving to instructional league. He had a 12.46 ERA in his first three professional starts for the Mustangs with six strikeouts and one walk while mostly facing batters who were several years older than him.
Greene said he expects to stay around three innings per outing for now. His workload will be closely monitored, something made easier with him just up the road in Dayton.
"I think I'm staying right around there, and continue to build up," Greene said. "Take it slow and make sure I'm healthy and ready to compete. Step by step."
The Reds haven't had many prospects like Greene, who graced the cover of Sports Illustrated as a high school senior called "the "star baseball needs." They've invested $7 million in the promise his right arm represents.
Last Reds general manager Dick Williams worried the Reds weren't selecting high enough to get Greene. They were picking second. Greene entered the 2017 draft as the top amateur pitching prospect in the nation, according to Baseball America and MLB.com.
"Not your average 18-year old" is how Greene often is described. He turns 19 on August 6.
When he was 10, Greene helped care for his younger sister, Libriti, who had been diagnosed with leukemia. Libriti, now 12, is in remission. He also defied the "dumb jock" adage as an honors student at Notre Dame High School in Sherman Oaks, California.
He embraces his celebrity and the responsibility that comes with it, and he doesn't shy away from the subject when asked about his role in luring more African-Americans to baseball. Greene is a regular participant at MLB's urban youth academy in Compton, California.
Greene, who attended the same high school as Giancarlo Stanton, Kirsten Dunst and Jerry Mathers, is a product of his upbringing, a mother who works in education and a father who is a well-known private investigator in Los Angeles.
Greene's fastball can reach 102. He has a power bat and great range in the field as a shortstop, although the Reds early on made the decision to develop him as a pitcher.
All of this has been well-documented. By the time Greene reaches the big leagues, there will be few if any secrets about him.
Last July, Greene received a $7.23 million bonus. Monday night kicked off the process of getting a return on that hefty investment.
"I still have a lot to work on," Greene said. "Continuing to pound the zone. Focusing on lefties more. I'm a lot more comfortable with the righty, but just understanding how to get a lefty out and be just as comfortable with that. Just stay healthy and continuing to compete."