A "very serious" ankle injury to Venezuela international midfielder Ronald Vargas marred proceedings in Newcastle Jets' 2-1 A-League win at Brisbane Roar on Sunday.

The in-form Roy O'Donovan gave the visitors the lead in the 12th minute, burying from close range to take his tally to five goals in three games, before a Nigel Boogaard own goal had seemingly ensured the hosts were to be level at the break.

But Dimitri Petratos scored against his former club to give the Jets a second on the stroke of half-time, smashing into the top-right corner from 30 yards.

The game will likely only be remembered for Vargas' horror injury, however, as the 30-year-old's ankle became trapped underneath him in a seemingly innocuous collision after an hour, forcing him to be carried off on a stretcher and taken straight to hospital.

Roar appeared to level again shortly after when Massimo Maccarone found the net, but the Italian's effort was ruled out by the video assistant referee and the Jets held on to all three points, continuing their unbeaten start to the season.

In the day's second game, Perth Glory enjoyed a late show for the second successive match, as they scored twice in the final 20 minutes to come from behind and beat Central Coast Mariners 2-1.

Andy Keogh cancelled out Wout Brama's opener, before Adam Taggart – whose stoppage-time equaliser against the Jets rescued a draw last time out – scored five minutes from time, springing the offside trap and applying a cool finish to secure a first win of the season.