Royston took an early lead with an easy chance after a miss kick from the Brentwood keeper.
The Eagles never let off the pressure bringing the score line level with a goal line scramble after a short corner routine with James Duggan slotting the ball home.
Duggan carried on his goal scoring ways with a first half hatrick taking his total to 22 for the season.
Going into the half time break 3-2 up Brentwood new they had a tough 35minutes ahead , probably the toughest this half of the season.
For twenty minutes the score line stood at 4-4 and Royston with their heads held high thought they had a chance to take the game and three points away from Brentwood. New signing Stephen Naven turned the game on its head and scored 4 superb goals.
With the home side depleted Brentwood pushed on and secured a further brace from centre midfielder Alex Henderson and veteran Simon Rattenbury.
This dramatic games saw 5 goals scored in the last fifteen minutes and a final score line of 9-4 to Brentwood.
A fantastic team effort from the squad sets a great stage for the New year.