After Jon recovered from Karyn's punch, he ran after them. By the time he made it to the park, they were already playing basketball. Well, Karyn and Tyler were playing (and Karyn was quite good, by the way). Jason was sitting on a nearby bench, viewing the personality manipulator device.
Jon stopped running to take a breath and it probably wasn't the best thing to do, because Jason noticed him. He got up from the bench and aimed the device at Jon, readying to shoot.
Jon looked all around him. He was in an open space, there was nowhere to hide. He was a sitting duck.
