The ART driver overtook Roman Stanek of Trident on the descent to turn 1, having a better start than the Trident driver.
He quickly gained a solid lead and, despite two safety machines, refrained from winning the third series.
Stanek took second place and took second place in the race, facing the challenges of Isaac Hajar of Hitech and Alexander Smolyar (MP Motorsport), who took third and fourth respectively.
A good start by Martins put him in the lead right ahead of Pole Stanek, and then Oli Birman of Prema Racing bypassed teammate Arthur Leclerc, who also lagged behind Cayo Cole (MP Motorsport) at the start.
Jack Crawford of Prem took two places before the first turn and finished seventh.
Hajar identified a place to take third place in Smolyar outside of Turn 1 and was close to bypassing Stanek ahead before stopping.
The safety car was deployed on the 4th lap after Rafael Vilagomes and Cush Maini (MP Motorsport) came into contact on turn 12, and the driver of Van Amersfoort Racing jumped over the gravel and into the barrier, finishing the race.
Minnie received a 10-second fine for the collision.
The race resumed on lap 8, and Jack Crawford bypassed Kahlen Frederick in sixth place in turn 1 before Colle followed him a few turns later.
Stanek, Hajar and Smolyar were involved in a tough fight for second place until the 10th lap, Martins was ahead for almost a second.
A second safety car appeared on the next lap after Brad Benavides of Carlina entered the barrier at turn 2, informing engineers by radio that he had a mechanical problem.
During the restart, Leclerc came into contact with the winner of the sprint race, David Vidales, who was forced to run into turn 1, and received a five-second penalty.
He dropped to 11th place before making his way past Gregoire Sosi (ART) before running into the width, trying to overtake Juan Manuel Correa for 10th place in an incident to be investigated after the race.
Correa bypassed Leclerc on the chicane, while racer Monagesque battled reigning European champion Formula Regional Saucy on the final laps.
On the penultimate lap, Martins was more than two seconds ahead and crossed the line 2.3 seconds ahead of Stanek.
Birman finished fifth, his second-best of the season: Crawford sixth and Cole seventh.
Franco Calapinta (Van Amersfoort Racing), Frederick and Correa closed the top 10, and Sosi took 11th place.
Formula 3 returns to Silverstone in support of the British Grand Prix from 1 to 3 July.
F3 Spain – results of the special race: