Alonso triggered the first red flag of day two in Bahrain testing after being forced to pull over and park his AMR26.
Another unlucky day for Aston Martin on the reliability front, after yesterday saw Lance Stroll caught out by an unusual spin caused by a technical issue that left him beached in the gravel and cost the team significant track time before he could rejoin.
A similar story unfolded for Alonso, with the Spaniard encountering an as-yet unidentified problem on the exit of Turn 2, losing the driveshaft completely and being forced to pull over and park his AMR26 at the exit of Turn 3.
Up to that point, Alonso had completed 45 laps — 40 of them during the morning session — and it remains unclear whether the mechanics will be able to repair the car in time for the final three hours of running.