Guelph scored first in the opening inning when Sean Reilly hit his ninth home run of the season off Red Sox starter Tanner Guindon.
The Royals scored runs in all but two innings, including a RBI doubles from Ethan Mohan, Josh Garton and Liam Hicks to bring the score to 5-0 before Brantford scored its only run of the game in the fifth inning after Sebastian Lech singled home Andris Rizquez who had reached on a walk and a stolen base.
Guelph added another run in the eighth on a wild pitch, scoring Mohan to make it 7-1.
Royals starter Yomar Concepcion put in eight innings of work, striking out 10 batters and walking five to earn the win. Brantford starter Tanner Guindon took the loss, going four innings and allowing four earned runs.