Red Bull's pre-season troubles continued on Wednesday after the Milton Keynes team failed to emerge from its garage on the first morning of the second official test in Bahrain.
The reigning Constructors' Champions completed only 21 laps at last month's four-day test at Jerez last month, but arrived at the Emirate state eager to get some time on track with their RB10 car.
With their new, updated Renault power units intact, both Lotus and Caterham were able to get some mileage into their cars on Wednesday morning, but Red Bull and Torro Rosso remained in their respective garages for the first three hours of the session.
Although neither team was available for comment about the situation, Red Bull advisor Helmut Marko told Crash.net that "it looks like" Sebastian Vettel will be able to spend some time on track before the end of the day.
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