Championship leader Lewis Hamilton outpaced team-mate Valtteri Bottas to top the times as Mercedes dominated Saturday morning’s third and final practice at this weekend’s Spanish Grand Prix.
The two ‘black arrows’ were separated by one-tenth of a second with Max Verstappen third, for Red Bull, half a second behind them.
Local hope Carlos Sainz was a strong fourth for McLaren ahead of Sergio Perez, back in action for Racing Point after missing two race weekends with Covid-19.
Charles Leclerc maintained his progress with Ferrari in sixth place ahead of Pierre Gasly of Alpha Tauri, Lance Stroll in the second Racing Point, Alex Albon in the second Red Bull and Daniel Ricciardo of Renault.
Four-time champion Sebastian Vettel was down in 12th for Ferrari as he continued to battle for form after a torrid start to the season.
On a hot morning at the Circuit de Catalunya, there was little early action in the dazzling sunshine and both Mercedes and Red Bull delayed their entry until midway through the hour.
As the early runners set their times, the air temperature was 29 degrees and the track was 43. Grosjean was soon busy lapping following overnight work on his Haas car, the American team having broken curfew to install engine components.
Sainz was also running new power unit parts in his McLaren.
Mercedes joined the fray with 30 minutes remaining and Bottas immediately topped the times ahead of six-time champion Hamilton with Verstappen going third when Red Bull sent him out.
Significantly, the Dutchman was only one-tenth off the Finn’s fastest lap and very close to Hamilton’s pace – a clear signal that Red Bull were likely to be competitive – before Sainz split the two Mercedes men with 20 minutes remaining.
Ten minutes later, Mercedes took softs and Hamilton restored a more familiar ‘black arrows’ one-two to the top of the times, the Briton outpacing his team-mate by just one-tenth.
The session ended abruptly with a red flag with two minutes remaining when Esteban Ocon swerved and crashed in his Renault as he moved to avoid Kevin Magnussen’s decelerating Haas exiting Turn Two.
The Frenchman, who was unhurt and walked away, appeared to be surprised by the Dane’s slowdown in front of him, prompting calls for a minimum lap time to be introduced to prevent similar incidents.