Despite a strong start to the first day of the second pre-season test, Honda has changed the engine in Stoffel Vandoorne's McLaren, the sixth engine change undertaken in five days of testing.

Neither McLaren nor Honda is saying anything, other than that the issue which necessitated the change was electrics related.

A difficult opening week of testing had McLaren team boss Eric Boullier admitting his frustration, the Frenchman - speaking for the team’s hundreds of thousands of fans in saying "this is not where we expected to be".

Following an original issue with the design of the oil tank, by any standard a fundamental error that should have been picked up long before the car hit the track, other problems arose over the course of the first week requiring no less than five engine changes,

Even ahead of this latest set-back, Honda's Yusuke Hasegawa has admitted concern that McLaren's start to the season will be compromised.

Only yesterday, it was revealed that the Japanese manufacturer has parted company with engine guru Gilles Simon, the man who had overseen Ferrari's engine programme during the golden era of Schumacher dominance.

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