Jake Hughes won the second Austria FIA Formula 3 race after on-the-road victor Robert Shwartzman was penalised for hitting fellow Ferrari Formula 1 junior Marcus Armstrong on the last lap
After encountering less degradation in Saturday's race than had been expected, the drivers appeared to push harder in the early stages of the second encounter.
Reigning German Formula 4 champion Lirim Zendeli led away from pole at the start, but a lock-up at the tight uphill right of Turn 3 was the beginning of a slide down the order for the Sauber Junior Team driver, with points leader Shwartzman and Hughes getting by to assume the fight for the lead.
Shwartzman's Prema Racing team-mate Armstrong then passed Hughes for second at Turn 9 on lap five of 24 to make it an all-Prema fight for the lead with Hughes watching on and staying within DRS range behind.
The fight moved the top three clear of the pack, with their lead increasing after a virtual safety car period came into effect on lap 12.
With five laps remaining, Armstrong set the fastest lap and moved out of DRS range to Hughes, allowing the front two to scarper away and fight for victory alone.
On consecutive laps, Armstrong passed Shwartzman at Turn 3, with the latter using the undercut and DRS to retake the position down the hill at Turn 4, before another VSC was activated after Campos Racing driver Alex Peroni took out his team-mate Sebastian Fernandez with three laps to go.
The VSC ended heading onto the last lap and Armstrong made another attempt at the outside of Turn 3, but the pair made contact with Shwartzman clipping Armstrong's right-rear, as the latter had got ahead entering the corner.
Armstrong went into the run-off as a result before dropping to 19th with a puncture.
"What is he doing?" Shwartzman asked on his radio before complaining again after the chequered flag.
Just after the race had finished, the Russian driver was given a five-second penalty over the clash, which handed the win to Hughes, who won this event when the championship was known as the GP3 Series last year.
Hughes, who secured HWA's first FIA F3 win, had finished just one tenth behind Shwartzman on the road.
Jehan Daruvala took second after successfully working his way through the order, making a key move to jump Max Fewtrell for fourth on lap 19.
Shwartzman ended up third after his penalty, with Fewtrell holding onto fourth ahead of the charging Leo Pulcini (Hitech Grand Prix).
Pulcini's team-mate Juri Vips fell down the order in the early stages, but he fought back to add sixth to his race one win, making a key move on Zendeli, which took him most of the race to complete, in the closing stages.
Niko Kari took the final point for Trident Racing in eighth, ahead of his team-mate Devlin DeFrancesco and Fewtrell's ART Grand Prix team-mate David Beckmann.
Results - 24 laps
|2||Jehan Daruvala||Prema Racing||4.727s|
|3||Robert Shwartzman||Prema Racing||4.850s|
|4||Max Fewtrell||ART Grand Prix||5.078s|
|5||Leonardo Pulcini||Hitech GP||5.665s|
|6||Juri Vips||Hitech GP||6.086s|
|10||David Beckmann||ART Grand Prix||10.172s|
|11||Yuki Tsunoda||Jenzer Motorsport||10.716s|
|12||Richard Verschoor||MP Motorsport||12.370s|
|17||Christian Lundgaard||ART Grand Prix||15.972s|
|18||Simo Laaksonen||MP Motorsport||19.677s|
|19||Marcus Armstrong||Prema Racing||19.863s|
|20||Andreas Estner||Jenzer Motorsport||22.026s|
|21||Giorgio Carrara||Jenzer Motorsport||23.867s|
|24||Alessio Deledda||Campos Racing||30.984s|
|25||Liam Lawson||MP Motorsport||1 Lap|
|26||Logan Sargeant||Carlin||3 Laps|
|-||Sebastian Fernandez||Campos Racing||Accident|
|-||Alex Peroni||Campos Racing||Accident|
|-||Yifei Ye||Hitech GP||Accident|