Kevin decided he wanted to improve the game a bit. He'd always been a big baseball fan, and had wanted to see a Major League game in person, but his father had always been too busy to take him. "Well," Kevin thought to himself, "if I can't go to a game, maybe I can make the next best thing!"
He focused his mind, trying to collect all the boys on both teams in his thoughts. He knew he couldn't actually make them full-blown major-leaguers, as that would make them older than 18 and thus he wouldn't be able to change them any more, so he decided to increase all the boys ages to be between 15 and 17. Using as much energy as he could muster, he slowly aged all the boys upwards by 8 years, leaving a bit of wiggle room.
He opened his eyes, and saw that the now-teenagers were playing, but the crowd was still pretty sparse, as the teams weren't very good, since the boys were just average teenagers. He decided he needed to make some more changes.
He grabbed every boy again with his mind and slowly increased their height to where they were all at least six feet tall, with the tallest among them reaching seven feet! He then looked out, and saw that the game was more crowded than before, with maybe five hundred people watching, but still not what he was hoping for. The boys were all very tall now, but were still mostly very skinny, not being able to hit very powerfully, and with only moderate athletic skill.
He then focused on adding muscle to all the boys. He didn't want to make them unnatural freaks like Barry Bonds, but gave them each a powerful upper body, and strong leg muscles, so they were all able to hit, throw, and run very well. He then focused on their reflexes and coordination, making them all super-responsive and skilled.
Now, when he opened his eyes, there was a whole different scene around him. Instead of being at a small field, they were now at a large stadium, with maybe ten thousand people in the crowd, not exactly a major league game, but incredible turnout for a bunch of high schoolers. He saw one boy, who was before the biggest kid in the game as a four-foot-eight, eighty-five pound eight year old, now stand an amazing seven-foot-two, two-hundred-eighty pound goliath. This boy, who Kevin realized was named Daniel, was the star of the team, and, indeed, of the entire country. Dozens of major league scouts were sitting down by the field watching him, and photographers from papers around the country captured his every at bat.
Kevin smiled. This was more like it; now he could see a good game! Mentally, he felt tired, but he could still make some changes if he wanted to.