In his junior year, something began to happen unexpectedly.
Reaves started to assert himself on the football field. As a senior, he was moved to linebacker, and the 6-foot-3, 185-pounder found a part of himself that he didn't know existed.
So complete was Reaves' transformation that he earned the Herald All-Area Defensive Player of the Year Award.
"When they moved me to linebacker, football took me over," Reaves said. "All of a sudden it was like a man's game, and I loved it. I was playing in the box and getting hit left and right. It was great. I knew then I liked football better than basketball because you can literally impose your will on an opponent."
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No one was happier than Manatee defensive coordinator Jim Phelan, who made the switch because of the potential he saw in Reaves.
"Greg made us real fast at linebacker. He is tall with long arms and gave us something we needed," Phelan said. "In the stuff we run on defense, he ends up man to man on a lot of backs and can stay with them. He is also physical enough to come up and make tackles."
Reaves was a backup to heralded safety Willie Smith in 2012. He became a starter for the playoffs when Smith injured his knee and was done for the season.
Reaves came in and did an admirable job, perhaps better than anyone expected. Phelan saw aggressiveness in him that was better suited for linebacker.
"At safety, sometimes he would come up so fast the running back would get by him. But Greg was perfect for linebacker," Phelan said.
Phelan also was pleased because Reaves was a vocal leader and very intelligent.
"You couldn't find a better person to coach," Phelan said. "After practice, he would come up and ask what he needed to work on. You only needed to tell him something once."
Reaves has a simple way of explaining why football overtook basketball for him.
"They call fouls in basketball. In football, when you touch someone they don't," he said.
Reaves touched a lot of people. He led the Hurricanes with 87 tackles, including a team-high 62 solos, and led the linebackers with six quarterback hurries.
"You feel a rush that goes through your body that you never get in basketball," Reaves said. "I like the crowd reaction. The big thing is that I liked linebacker better than safety. It changed me."
Reaves hopes to become the first person in his family to play football in college. He has received an offer from the University of Albany in New York, and others may come.
He is on the young side. Reaves doesn't turn 18 until August and would've been eligible to play another year if he hadn't started school so young. But it could be an upside for college. He has a lot of room to put muscle and weight on his body. Either way, Reaves is excited about playing in college and appears to have unlimited potential because of his youth.
"He was our defensive MVP and has a 3.5 GPA," Phelan said. "I see great things for him at the next level."