Carlos Sainz edged Lando Norris to victory in another intense practice session ahead of qualifying for the Spanish Grand Prix.
The top four were separated by less than a tenth of a second, with Charles Leclerc in third and Max Verstappen in fourth, but the session ended in drama at the end when Leclerc made contact with Norris.
Leclerc was doing a fast lap and seemed unhappy at being interrupted by Norris, so he slowed down, moved left and made minor contact with the McLaren driver.
Moments later Leclerc, Verstappen and Sainz were all almost tangled up, resulting in the first Leclerc-Norris incident, which is being investigated by stewards.
Mercedes' George Russell and Lewis Hamilton finished fifth and sixth, but both drivers will be targeting pole in qualifying at 3pm. Sky Sports F1 and Sky Sports Main Event.
Before the final practice, McLaren's hospitality was on fire. Sky Sports News Fire authorities believe that at least two firefighters received treatment for smoke inhalation, but their condition is not serious.
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Ahead of Practice 3 and qualifying, an evacuation of the paddock was called after a fire broke out in a McLaren hotel suite.
narrow margin on front
Throughout the weekend, there was little separation between Ferrari, McLaren, Red Bull and Mercedes, even though the gap at the front was expected to widen due to the track layout.
Sainz was 0.030 seconds ahead of Norris in the final soft tire run of final practice, while Leclerc was 0.037 seconds behind his Ferrari team-mate.
Verstappen, who has a fourth powerplant in his car this weekend and is on the verge of needing a grid penalty for using the fifth engine, was 0.074 seconds behind Sainz but has shown he can produce when it matters most this year.
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Anthony Davidson analyzes the confusion that arose in Exercise 3.
Russell set the pace throughout the session but fell 0.174 seconds behind to fifth, while Hamilton was unable to record a clean lap and fell to sixth.
Sergio Perez was handed a three-grid place penalty for Sunday's race after returning to the pits with a damaged rear wing last time out in Canada, and his lack of form throughout the weekend could see him start in midfield.
The Mexican was three-quarters of a second slower than Sainz and ahead of Williams' Alex Albon, Aston Martin's Fernando Alonso and McLaren's Oscar Piatri.
Multiple drivers under investigation
Leclerc will be hoping to repeat his Monaco heroics, converting pole into victory, but could face a grid penalty.
The swerve towards Norris on the run into Turn Seven was described as a moment of “road rage” by Sky Sports F1's Karun Chandhok.
He is meeting the stewards to explain his actions after becoming frustrated with Norris' alleged blocking, and on his way down to turn 10 he found Verstappen and Sainz also having their own incidents without crashing.
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Lewis Hamilton and Lance Stroll collided with each other on the track during the third practice session of the Spanish Grand Prix.
Earlier in the session, Lance Stroll had a similar incident where he contacted Hamilton while expressing anger over the alleged obstruction.
They will also meet the stewards ahead of qualifying.
sky Sports F1's live Spanish GP schedule
Saturday, June 22nd
1:10 PM: F2 Sprint
2.10pm: Preparing for Spanish GP qualifying
3pm: Spanish GP qualifying
5pm: F1 Academy Race 1
Sunday, June 23
7.45am: F1 Academy Race 2
9am: F3 Feature Race
10:30 AM: F2 Feature Race
12.30pm: Grand Prix Sunday: Build-up to the Spanish GP
2 p.m.: Spanish Grand Prix
4pm: Checkered flag: Spanish GP reaction
Formula 1 returns to Europe as the championship moves to Barcelona for the Spanish Grand Prix and the start of a tripleheader. Watch every session of this weekend's Circuit de Barcelona-Catalunya live on Sky Sports F1. Stream every F1 race and more with a NOW Sports Month membership. There is no contract and you can cancel at any time.
