The session was red flagged for 35 minutes with Sebastian Vettel's Aston Martin stricken on the side of the track after suffering an engine failure. After the stewards and team eventually got it moved only six minutes of the session remained and from then it was chaos. Times tumbled as the drivers looked to get as many laps in as possible.
Ferrari went top with a one-two, and then Mercedes led but the top three eventually settled with Max Verstappen sandwiched between Hamilton and Sainz.
It was a frustrating session for the teams though as they would have been hoping to get as much data as possible.
Charles Leclerc was fourth with Bottas eventually finishing fifth. Fernando Alonso was sixth and
Esteban Ocon (P7),
Antonio Giovinazzi (P8),
Lance Stroll (P9) and
Pierre Gasly (P10) completed the top ten.
Kimi Raikkonen finished 13th in his first session since announcing he will retire at the end of the season.