Alonso: Aston Martin and Honda underestimated Mexico 'moment of truth'

Fernando Alonso believes Aston Martin and Honda underestimated the “moment of truth” posed by the Mexico City Grand Prix after power unit failures wrecked both cars. A promising weekend collapsed in qualifying and the race, leaving the team with a hard lesson in reliability under extreme conditions.

Why it matters:

Mexico is one of the season’s toughest power-unit tests. At 2,285 metres above sea level, air density is roughly 20% lower, forcing turbos to work harder. With the MGU-H removed from 2026 engines, teams have lost a key tool for managing turbo lag.

The details:

• Alonso stopped in qualifying after one flying lap with a water pressure issue, despite expecting to challenge for Q2.
• Both he and Lance Stroll retired after five laps, with Aston Martin citing “abnormal pressure levels in the PU systems.”
• Practice had offered hope: Alonso was seventh in FP1, Aston Martin’s best session result of the season.
• Alonso said the altitude challenge was “probably underestimated by the power unit,” calling the failures a shared problem.

What’s next:

Aston Martin and Honda must turn Mexico into a reliability lesson rather than a recurring weakness. The practice pace suggests potential, but frequent retirements will quickly drain momentum in 2026.