( CNN ) -- The score was tied . The game was in overtime . The mood , electric . Number 35 came charging up to the net and hit a last-moment winning layup for his undefeated Fennville High School Blackhawks to end the regular season Thursday night with a perfect 20 wins . The other players hoisted their star , 16-year-old Wes Leonard , on their shoulders . The screaming crowd charged the court to hug him . It was the biggest moment in memory for the tiny Michigan town of Fennville . And then it all turned to black . Silence fell under the harsh glare of the florescent lights . Leonard lay still on the court , pale in his school colors . His family and coaches surrounded him . He was n't breathing , his friend Arista Sauceda recalled . His heart had stopped cold . After attempts to revive the varsity player in the gym , an ambulance transported him to nearby Holland Hospital . Doctors worked on him for an hour and 20 minutes . They could not save him . By 10:40 at night , when Leonard should have been out celebrating with his classmates , he was dead . An autopsy Friday determined that Leonard died of cardiac arrest due to an enlarged heart , said a statement from Dr. David A . Start , the Ottawa County chief medical examiner . As news of Leonard 's death spread , a small community on the banks of Lake Michigan convulsed in shock . A moment of enormous school pride was reduced to irrelevance , a moment of joy turned into the opposite . A Facebook memorial page -- R.I.P . Wes Leonard -- created Friday , quickly filled with thoughts and prayers . `` Blackhawk Down , '' the page said . Sauceda described Leonard as an affable guy , popular for his smile and jokes . He excelled in athletics , scoring 1,000 career basketball points and playing quarterback for the school 's football team . She said Leonard 's family moved to Fennville when he was in middle school . His mother , Jocelyn Leonard , teaches music and is the drama director at Fennville , and Sauceda said the family had helped bring the school community together . Jocelyn Leonard had canceled Thursday night 's performance of `` How To Succeed In Business Without Really Trying '' because she wanted to watch her son play in the game , reported CNN affiliate WOOD . It was a make-up game to compensate for blizzard-canceled events last month . Everyone had so looked forward to Thursday 's game -- not only was it the last of an undefeated regular season , but it pitted Fennville against Bridgman , a school that beat them by just one point last year . It was revenge , as Sauceda put it . Fennville was down 14 points but came back to tie the game at 53 . Leonard scored his team 's last four points for the 57-55 victory . Sauceda had screamed her lungs out during the game . She was running toward Leonard to hug him when he went down . Tim Breed , a spokesman for Holland Hospital and a 1977 Fennville graduate , was also in the gym . He does n't normally attend games , but thought he could not miss his alma mater 's perfect season closer . When Leonard collapsed , the crowds were asked to leave the gym . Breed was on his way home when he was paged by a local newspaper reporter . He rushed to the hospital to find medical teams trying to resuscitate Leonard . Shortly after that , a text message appeared on Sauceda 's phone from a friend at the hospital . Sauceda was about to go to sleep . Instead , she was jolted awake , the shock so severe she was n't even able to immediately cry . In the morning , she stayed home from school . And wrote on Facebook : . `` Wes , you were taken from our lives too soon ... you were the most amazing friend , I will never forget you , and how you have changed us all , I am so thankful to have been apart of your life . Please watch over us , and cheer us on as our boys win state ! RIP # 35 WES LEONARD . ''
Wes Leonard was a star athlete and a popular student . He had been accepted to the University of Michigan, but he decided not to attend because his parents were poor. He collapsed on the court after the game . A small Michigan town is in shock .