Mercedes entered qualifying chasing only its second pole of the season after finishing 1-2 in FP3, but ultimately lost out to Red Bull’s Max Verstappen in Q3 at the Autodromo Hermanos Rodriguez.
Verstappen beat Russell and Hamilton to pole by three tenths of a second as both Mercedes drivers struggled in their final Q3 runs.
Russell called his last lap “terrible” after running wide at Turn 12 and failing to improve his time, while Hamilton revealed after the session that he felt an engine issue in Q3. He qualified third, five thousandths of a second off Russell’s time.
Hamilton said it was “generally a good qualifying session” with “no major issues”, but he felt the engine problem did cost him a bit of performance.
“We had some problem with the engine towards the end and in Q3,” he said. “So, I definitely think there was performance left on the table. I did the best I could.”
Hamilton explained that the issue “started to appear in Q2” and was then occurring on “every run in Q3, basically dropping out of power on exits from corners.”
He added: “I do think we were losing quite a bit of time I think out of the last corner and basically out of most of the corners. It felt like an ignition issue. But, I’ll find out from the team.”
Asked by Motorsport.com about the issue, Mercedes team principal Toto Wolff said there was an “oscillation” that had been spotted on Hamilton’s engine.
“That badly affects drivability,” said Wolff. “So it definitely affected his lap.”
Hamilton’s only valid time of Q3 was set on his final lap after his first effort earlier in the session was deleted due to exceeding track limits at Turn 2, setting a time that would have been one-hundredth of a second slower than his second effect.
Hamilton explained that losing the first lap made his second one “very hard” as he ensured he did not breach track limits again and risk setting no time at all, which would have left him 10th.
“I had to be very reserved on that last lap, just to make sure that it was clean, because I was a tenth up to that point,” said Hamilton. “Unfortunately, [I was] not able to push as hard as I’d have liked.
“Nevertheless, I think it’s a good result for the team, second and third. It’s no bad position to start.
“I hope we can fix the problem on Sunday.”
