Thomson finished with a two day total of 136 (64-72).
It's Thomson's second straight win at the NYSGA Junior Boys Championship. He is eligible to go for a 3-peat next year.
Next up for the Pittsford native: the US Men's Amateur Championship from Atlanta Athelic Club next week.
Thomson began his triumphant push during Tuesday's opening round. An 8-under 64 put him up by 11 shots. Wednesday, Thomson was steady and still able to gain another 10 shots to his lead.
In his opening round, Thomson birdied 9 holes, including five in a row on the front 9. His only blemish came with a bogey on 12. On Wednesday, Thomson finished with 3 birdies and 3 bogeys.
If Thomson wins next year, he'll be the first to win the NYSGA Junior Boys Championship three years in a row. Alec Bard, Gavin Hall, and Nick Park have each won it twice.
Kevin Gilroy of Manlius finished 2nd at 157 (80-77). Tied for third was Aidan Shaw of Orchard Park (80-78) and Ryan Zogby of New Hartford (75-83) at 158.
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