The two day clinic at Mosley was attended by approximately 200 kids aged 10 to 18.
42 boats are entered for the 15th annual tournament.
Boats leave on Friday morning, one day behind the original schedule.
The fleet will leave Friday and the weigh ins are now set for Saturday and Sunday.
So far this season, Nelson had made nine starts, touting an 0-6 record with a 6.34 ERA with Single-A Charleston.