The 16-year-old's natural speed and athleticism now have him pursuing basketball stardom, a dream that is becoming more achievable in a country that produced one of the NBA's greats but, like most of Africa, has had little space for any sport other than soccer.
About 30 years after Hall of Famer Hakeem "The Dream" Olajuwon first emerged from the sprawling city of Lagos, Ayetimiyi is part of a new drive for basketball here, and a chance for new dreams in Nigeria.
"In my country I'm known here, but I want to be known elsewhere. I want my hard work to be seen by agents, coaches. I'd like to finish high school in the U.S. They don't need to put much work into me," the teenager said with a grin, leaning forward to make his point.
Picked by the NBA as one of seven Nigerians to attend the recent talent-scouted Basketball Without Borders camp in South Africa, Ayetimiyi is among a new generation ready to ride the momentum basketball is gaining in this West African country of nearly 160 million people, albeit decades after Olajuwon blazed a trail.
Nigeria's participation in the 2012 Olympics raised the international visibility of the country's basketball talent, but several Nigerians who had already made it to international stardom also make it a priority to actively encourage the sport back home.
First came Olajuwon, the two-time NBA champion and 12-time All-Star with the Houston Rockets. More recently there has been Toronto Raptors General Manager Masai Ujiri, who directs the Basketball Without Borders Africa program and runs his own camps in Nigeria. And former Seattle Supersonics and Orlando Magic centre Olumide Oyedeji.
On a steaming hot Friday in the Yaba neighbourhood of Lagos, Oyedeji coaches at least 250 kids from the age of five and up who practice layups, passes and basic dribbles wearing brightly colored T-shirts.
The 6-foot-10 Oyedeji plays with them, towering over the youngsters who line up laughing and clapping for each other around four different baskets. With the blow of a whistle, everyone stops and listens, excited to be in his gentle, inspiring presence. The subsidized camp gives the underprivileged kids a chance to learn the sport, and be close to a Nigerian hero.
"Nigeria is my home. I started this camp so I can share my experiences," Oyedeji said. "I hope we can contribute to their lives and give them hope for the future because that's what basketball gave me. I had a difficult childhood."
Kids gather close, hanging on Oyedeji's words. Oyedeji will leave soon for Japan, where he now plays. But his impact will remain, for girls as well as boys.
"Even though we (girls) are not recognized very well, we can still play. I want to be the best and play for the WNBA," said 15-year-old Ibeh Lucy Chinelo, who started a pickup game during the camp's lunch break.
Her friend Ayomide Olukayode chimed in: "I want to be a professional player and I want to play for the national team."
Nigeria is offering more local opportunities: high school teams, university leagues and state franchises like Mark Mentors, Kano Pillars, Union Bank and Dodan Warriors, who faced off at Nigeria's own Final Four in September.
Dodan Warriors forward Ifeanyi Modo started playing at a local court in Ajegunle, a Lagos neighbourhood known for churning out soccer players, though also known for its slum areas and gangs.
"Basketball gives you an opportunity to get off the streets, it gives you an opportunity to not join gangs, to go to school and to be a better person," he said. He said that many Nigerians leave to play in other countries "because they need money, they need to support their families."
The reality right now is the average salary in the Nigerian league is only about $100 a month, said Joe Touomou, the Mark Mentors head coach and a consultant to the Nigerian Basketball Federation, the NBBF — "not enough for a kid to live off."
Touomou is part of a bigger plan to encourage youngsters to seek careers in basketball. That involves the promised land of playing for college teams in the United States and the chance for two things; better coaching and a good education — opportunities Olajuwon seized in the early 1980s at the University of Houston, and others have also more recently taken. Yet, not all Nigerian kids will make it to an American college so there's work being done at home, too.
Nigeria's Basketball Federation wants to foster local talents. Touomou, a Cameroonian who played for Georgetown and turned to coaching after an injury, is also tasked with building coaching expertise in the capital Abuja and its surrounding state.
"Every time I came here I was impressed by the potential. The size, the athleticism, the strength of the players," Touomou said of Nigeria. "The one thing I knew was lacking was the skills. A lot of players were not polished yet, a lot of players lacked game experience, a lot of players lacked good coaching."
Tijjani Umar, president of the NBBF, said basketball in Nigeria "needs the private sector to take interest."
Nike has signed to be the official uniform provider for the national team and a subsidiary of the sports management group IMG is looking into Nigeria, Umar said.
DSTV, a South African satellite television network that beams across the continent, has a four-year sponsorship program with the NBBF. Live NBA games will also be broadcast on that network to 47 territories in Africa, including Nigeria, from this year.
"Fifty countries are watching the game and it's unbelievable," Umar said.
Young hopeful Ayetimiyi leaps high to dunk in Lagos, then dribbles the ball back to centre court, skipping with pleasure in his shiny sneakers and sharp, white long-sleeved Basketball Without Borders jersey.
Basketball's exposure on TV is what changed his father's opinion.
"My parents saw me on TV during a state festival game and said I was too good to stop playing," he said. "They were proud of me, and I'm lucky I have their support."
He circles back to the court, grins, dribbles and goes for another layup, believing every shot he makes can take him closer to his dream of international basketball stardom.