The Prema Racing rookie had his debut win taken away after he was awarded a five-second penalty after crossing the finish line, handing victory to fellow newcomer Isack Hadjar.
Celebrations by the team were cut short after the penalty pushed the Briton into second place, giving the 10 points for the win to the Hitech Grand Prix driver instead.
But Bearman says he was only aware of exceeding track limits once, on the penultimate lap, and “apart from that I was pretty sure I was on the white line or leaving some margin”.
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Despite the “bittersweet” ending to his season opener, the 16-year-old Ferrari Driver Academy member said he was “still quite happy with the result”.
Bearman said: “I didn’t actually find out about the track limits until after the race, so that was a bit of a shame.
“Anyway, still quite happy with the result, we had good pace, I made a decent start, managed to pass on track into the lead, then after that I was just managing the tyres and doing the distance.
“Bit unfortunate to get the penalty but still we showed we can win on track and just need to iron out those mistakes.”
He added: “I knew I did it once for sure on the penultimate lap, I definitely went wide, but apart from that I was pretty sure I was on the white line or leaving some margin.
“I didn’t actually know about the penalty until after the race had finished, which was quite bittersweet, but anyway.”
Bearman crossed the line 3.4s ahead of Hadjar after passing polesitter Zak O’Sullivan for the lead on lap five of 20.
The Carlin driver eventually finished the race sixth, having suffered tyre issues.
Hadjar, who started fourth, said he “wasn’t aware at all” of Bearman exceeding track limits during the race, adding that it was “a shame” not to get his first series win on track.
He said: “It feels very nice, it’s a shame that we didn’t get that win on track but we definitely had the pace to win it if we didn’t have those fights in stages of the race, but it’s a good start to the season for sure.”
He added: “I wasn’t aware at all during the race, I got a radio message from my engineer saying ‘you won the race’ and I didn’t know why, he just told me he has a five-second time penalty.”
F3 returns to the Bahrain International Circuit on Sunday for its feature race.
