Having suffered a difficult start to his rookie season, the 2021 FIA Formula 3 champion finally clinched his first win of the year for Prema in Saturday's sprint race.
With Hughes failing to get off the line in his Van Amersfoort Racing-run car, Hauger made it past and held fast until the chequered flag, having built up a five-second lead.
teammate Jehan Daruvala made it a Prema 1-2, with Marcus Armstrong taking his second podium of the season for Hitech Grand Prix.
Despite Hughes' stall on the grid parking him in the path of the rest of the pack, the remaining 20 cars made it past without any major incident.
The top four were boosted a place, while further back, having made it through the melee, 2021 race winner Theo Pourchaire passed Jack Doohan for sixth place down to Mirabeau.
The safety car was deployed on lap 10 after MP Motorsport's Clement Novalak ended up in the barrier at the exit of La Rascasse, with Ayumu Iwasa having made contact while trying to dive up the inside. The DAMS driver received a 10-second penalty for the incident.
Racing resumed on lap 14, and though Enzo Fittipaldi looked keen to pass Armstrong for third, the Charouz Racing System driver was forced to stay behind, fending off challenges from Juri Vips in fifth.
By lap 23, Hauger had built a five-second lead to Daruvala, having taken several fastest laps on his charge to victory.
But he was pipped to the bonus point by Doohan, who set a 1m22.832s on the final lap to finish in seventh.
Liam Lawson, who was stripped of pole for tomorrow's race because of a yellow flag violation, took eighth, with Roy Nissany (DAMS) and Carlin's Logan Sargeant rounding off the top 10.
Championship leader Felipe Drugovich was forced to pit after suffering a rear right puncture in the opening chaos, with his MP Motorsport team taking a gamble and sending him back out on the wet tyres.
But he pitted again just two laps later after their risk failed to pay off and received a five second penalty for speeding in the pitlane.
He had appeared to retire but returned to the track five laps behind the pack before receiving another penalty for the same reason several laps later, with confusion ensuing over whether he was to continue or stop racing.
Sunday polesitter Drugovich finally retired on lap 19, marking a double DNF for the Dutch team.
Campos Racing's Ralph Boschung was forced to withdraw ahead of the race due to ongoing neck pain which also saw him pull out of the Barcelona weekend.
He qualified seventh in Group A on Friday but decided not to race, saying in a social media post that his "health situation has not been getting much better" and that he was "not able to push at my full capabilities in order to get the result my team deserves."
F2's feature race takes place on Sunday at 08:50 BST (09:50 local time).
| Cla | Driver | Team | Gap |
|---|---|---|---|
| 1 |  Dennis Hauger |  Prema Powerteam | |
| 2 |  Jehan Daruvala | Prema Powerteam | 6.700 |
| 3 |  Marcus Armstrong |  HitechGP | 7.200 |
| 4 |  Enzo Fittipaldi |  Charouz Racing System | 13.100 |
| 5 |  Jüri Vips | HitechGP | 14.500 |
| 6 |  Theo Pourchaire | ART Grand Prix | 15.800 |
| 7 |  Jack Doohan | UNI-Virtuosi | 1 Lap |
| 8 | Liam Lawson | Carlin | 1 Lap |
| 9 |  Roy Nissany | DAMS | 22.800 |
| 10 |  Logan Sargeant | Carlin | 1 Lap |
| 11 |  Frederik Vesti | ART Grand Prix | 26.300 |
| 12 |  Cem Bolukbasi | Charouz Racing System | 31.300 |
| 13 |  Richard Verschoor | Trident | 32.400 |
| 14 | Calan Williams | Trident | 44.200 |
| 15 |  Marino Sato | UNI-Virtuosi | 44.600 |
| 16 | Olli Caldwell |  Campos Racing | 45.200 |
| 17 |  Amaury Cordeel | Van Amersfoort Racing | 47.200 |
| 18 | Jake Hughes | Van Amersfoort Racing | 55.400 |
| 19 | Ayumu Iwasa | DAMS | 55.700 |
| Felipe Drugovich | MP Motorsport | ||
| Clement Novalak | MP Motorsport | ||
| View full results | |||
