The Ronins fell to 6th place (25 points) in the Yamaha League-1 standings with the loss.
In the sixth minute, Ayutthaya's Nigerian midfielder Adefolarin Durosinmi scored off a rebound shot to take give his team a lead they would not relinquish.
In the second half, striker Premvut Wongdee added a second goal. Michael Byrne scored the third tally in stoppage time.
The game was physical all throughout with seven players (from both teams) acquiring yellow cards for tough tackles.
This was the fifth game in two weeks for the Ronins and have tallied two wins, 1 draw, and two losses in that span (including a 1-0 loss to Thai Premier League's Bangkok Glass last Wednesday in the Toyota League Cup).
The team announced that an exhibition match will take place this Thursday (June 19) against Phangnga FC at Surakul Stadium at 4pm.
The Ronins' next Yamaha League-1 match takes place at home next Sunday (June 22) against Gulf Saraburi FC who are currently 5th (25 points) on the table and are only above Phuket FC on goal differential (+6 to Phuket's +2). Kick off at 6:30pm.