After notching a hat-trick in his previous match, Davila gave the Bulls the lead in the 16th minute at Suncorp Stadium and was influential in the lead-up to fellow forward Raphael's second-half strike.
The win was the Bulls' first in seven matches and took them to fourth place on the ALM ladder.
Davila and right winger Jed Drew combined superbly throughout the match, which was played in driving rain.
Drew, 20, has struggled with his end product, but came to the fore with an assist for Davila's goal and one of his own.
In the 16th minute a blunder at the back by Roar defender Ryan Lethlean conceded possession to Drew, who cut the ball back to Davila.
The skipper calmly sidefooted it into the corner of the net, giving Roar goalkeeper Macklin Freke no chance.
In the 53rd minute Davila combined with Drew, who found Valere Germain wide on the right. Germain's pinpoint cross was finished by Raphael.
Six minutes later Raphael hit the post, and hungry Drew was there to make it 3-0.
Roar forward Jonas Markovski got one back for his side, but it was too little too late.
Brisbane substitute Keegan Jelacic, in his first game back in the ALM after a stint in Belgium, was given a red card in the closing minutes for a rash challenge on Clayton Lewis.
Attacking midfielder Florin Berenguer had earlier failed a late fitness test in a blow to the hosts.
Brisbane started the game with plenty of intent, but lacked polish in the box.
Roar winger Nikola Mileusnic had a clear view of goal from close range in the 47th minute, but missed the target.
It was the story of the night for Brisbane, who lost their third game in a row at Suncorp for the first time since 2019.
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