The Australian driver carved his way through the field in a fine performance to finish fourth after 26 laps. Luke Browning won from Gabriele Mini, Dino Beganovic, and Mansell.
Mansell spent the final laps battling for the podium, wisely keeping his nose clean in what was a frantic scrap that could have easily left him with nothing.
A slow start from Tim Tramnitz saw the third-placed starter fall to seventh as Browning held the lead from Arvid Lindblad and Mini.
Mansell dropped a spot in the opening exchanges to end the opening lap 12th.
Beganovic was on a charge in the opening moments, rising to second at Turn 3 on Lap 2 after starting fifth.
Mansell was in the thick of the midfield battle, climbing to 11th over Laurens van Hoepen on Lap 2 but was shuffled back a lap later as the Australian dropped to 13th.
The top 28 drivers all ran within DRS range of the car ahead, making for a constant ebb and flow of drivers in the pack.
Tramnitz was in the thick of it, catching the eye of Mansell who radioed that his rival was being “a bit naughty” – he was later slapped with a time penalty for his antics.
The Novocastrian had risen to 10th in the wheel tracks of his ART teammates Nikola Tsolov and van Hoepen as they completed Lap 9.
That became ninth at Turn 4 on the next lap as he moved underneath van Hoepen at the downhill right-hander.
A collision between Nikita Bedrin and Mari Boya left the former pointing the wrong way at Turn 3 on Lap 11, drawing the Virtual Safety Car.
The stricken car was quickly cleared and racing resumed without the need for further intervention, leaving Browning clear out front from Beganovic and Mini.
Mansell remained ninth, though had dropped back off Tsolov during the Virtual Safety Car by some two seconds.
A puncture for Noel Leon saw him fire off the road at Turn 5, doing well to keep the car moving through the gravel to avoid a second interruption to the race, handing Mansell another place.
There were plenty of penalties being dished out for causing a collision, Alex Dunne in fifth the highest placed of those to pick up a 10-second penalty.
After 15 laps, Mansell was running eighth on the road, though an effective seventh given Dunne’s looming penalty.
He had reeled in the pack ahead, reducing the gap to be within DRS range of Tsolov as they started Lap 16, moving by on Lap 17 to take seventh. That became sixth when he went around the outside of Lindblad at Turn 4 on Lap 19.
Next in Mansell’s sights were then set on McLaren junior Dunne, repeating the move he put on Lindblad to steal fifth.
He then joined the queue at the front of the race, headed by Browning from Beganovic, Mini, and Oliver Goethe in fourth.
A dive at Turn 3 on Lap 22 saw Mansell ambush Goethe to take the place and move within one place of the podium.
Next time around, a mistake from Mini compromised his exit at Turn 3, though Mansell was also suckered into running wide as they held station in third and fourth respectively.
Mini attacked Beganovic for second on Lap 24 but could make the move and came under immediate attack from Mansell, who went around the outside of Turn 4.
It was short-lived as Mini went back around the outside at Turn 5 to regain third.
Their battle allowed Goethe back into contention with Dunne tagging along in sixth on the road – though with a time penalty hanging over him.
Mini and Beganovic swapped places at Turn 5 on the penultimate lap as Mansell maintained a watching brief.
The pair were at it again at the star tof the final lap, Mini looking up the inside but unable to make it stick.
Mansell attacked up the inside into Turn 4 as Mini and Beganovic went three-wide but wisely backed out of it
Browning held on to win with Mini second from Beganovic and Mansell, who’d put in arguably the drive of his F3 career.
The 19-year-old is now fifth in the championship standings with the competition in action next weekend in support of the Formula 1 British Grand Prix.