In what was a closer session than first practice, where Hamilton was almost two seconds clear of the fastest non-Mercedes runner, the top three drivers were covered by less than three tenths of a second.
Daniel Ricciardo was second fastest, splitting the Mercedes, while his Red Bull team mate Max Verstappen completed the top five, lapping Circuit of the Americas eight hundredths of a second slower than Sebastian Vettel.
Bahrain International Circuit - Winter testing
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