A second-half hat-trick by teenage striker Cyrus Dehmie has fired Brisbane Roar into the FFA Cup quarter-finals for the first time in the A-League Men club's history.

Dehmie scored in the 50th, 78th and 84th minute as the Roar claimed a comfortable 4-0 derby win over NPL Queensland outfit Lions FC at Richlands on Sunday.

The 19-year-old was the standout performer in the clash between the Roar and the club from which they emerged in 2004 for the inaugural A-League Men campaign.

It was Dehmie who was fouled inside the opening 10 minutes to win a penalty for the Roar which was confidently converted by fullback Corey Brown to give Brisbane early control in scorching conditions.

Brown capped his goal with a classy celebration, running to the sideline before holding up a jersey bearing the number of teammate Izaack Powell - who is battling leukaemia.

That strike was all the Roar could manage in the opening half, with experienced defender Jack Hingert limping off on the half-hour mark in a setback for coach Warren Moon.

The Roar showed their class in the second-half however, with Dehmie's pace getting him repeatedly in behind a tiring Lions defence.

His first strike early in the second-half was a cool finish after sprinting clear before he added a second with a clever chip which left Lions goalkeeper Luke Borean clutching thin air.

Dehmie wrapped up his hat-trick in the final 10 minutes, again getting behind the defence before firing a bouncing ball powerfully past Borean.

The victory means Brisbane are into the last eight of the FFA Cup for the first time as Moon chases his first piece of silverware as Roar coach.

Holders Adelaide United reached the quarter-finals last weekend with a 1-0 win over Adelaide City.