"It's difficult to remember a day that is darker than this one," National Baseball Congress General Manager Kevin Jenks told NBC News. "Kaiser was simply doing something he loved."
Kaiser Carlile, a bat boy for the Liberal Bee Jays of Liberal, Kansas, was running to bring a bat to a player after an out on Saturday in a game against the San Diego Waves in Wichita when he was struck in the head by a batter doing a warmup swing, NBC reports.
Nathan McCaffrey, president of the college summer league team, told CNN that he heard the bat collide with Kaiser – who was wearing a helmet – before he stumbled backward and fell.
An umpire gave the boy first aid until first responders arrived, NBC reports.
Carlile had been in critical condition since the tragic accident and, early Monday, the team made the heartbreaking announcement on Facebook.
The statement reads in part: "With the permission of the family, and with much sorrow and a very broken heart, I regretfully inform everyone that Kaiser Carlile passed away earlier this evening."
The Liberal Bee Jays kneel in prayer after discovering the tragic news of Kaiser Carlile's passing after the game. pic.twitter.com/OEMrHXiQrU— Taylor Eldridge (@teldridge24) August 3, 2015
The 9-year-old had been a bat boy for most of the team's season, CNN reports. And a photo posted to Twitter by a local reporter shows the team kneeling in prayer after the game upon learning of Carlile's death.
The game was part of the National Baseball Congress World Series. The Bee Jays went home with a very emotional win.