Mercedes have backed the decision to highlight the potential consequences of dirty driving before the Formula 1 title decider in Abu Dhabi.

Mercedes F1 boss Toto Wolff said it was “a good deterrent for everyone”.

Red Bull team principal Christian Horner called for consistency of decisions.

Red Bull’s Max Verstappen and Mercedes’ Lewis Hamilton are tied on points and whoever finishes ahead in the race will emerge as champion.

However, Verstappen would win the title if both retire or crash out together, as he has one more victory than Hamilton.

The FIA’s decision to highlight clauses in the sporting code in race director Michael Masi’s event notes before the weekend is seen as a warning to the drivers to race cleanly on Sunday.

And the race at a remodelled Yas Marina track takes place a week after a bad-tempered and controversial Saudi Arabian Grand Prix in which Verstappen was penalised three times for driving infringements, once for overtaking off the track, once for forcing Hamilton off the track and once for braking in front of his title rival and precipitating a collision.

Hamilton set the pace in Friday practice, with Verstappen in fourth place, 0.641 seconds behind.

Wolff said: “I think with all the controversies we had in the last few races, it is very good that Michael and the FIA have come out with a reminder of what the ISC [international sporting code] stands for.”

He welcomed the decision to remind the drivers “what is on and what is not on, in terms of driving standards”.

Horner said: “I can see why Toto and Lewis with the disadvantages of race wins would be pushing for that, but nobody’s going into the race saying it’s going to end in a crash.

“There has been great speculation about it but our focus is on trying to win this on track and do it at the chequered flag.”

He added: “There has to be consistency of stewarding of penalties and that is the thing that drives people more mad than anything else, when there is perceived to be an inconsistency.

“That piece of the sporting code has always been here. Nobody wants to see this championships end up in front of the stewards.”

Horner’s remarks are a reference to the fact that in Brazil three races ago Verstappen was not penalised for forcing Hamilton off the track when defending his position and in Saudi Arabia he was.

Verstappen said on Thursday that he does not think he has been treated equally by the stewards in comparison with other drivers and that he sees no reason to change his driving.

What happened in practice?

The significant time gap between Hamilton and Verstappen over one lap suggests that the headline lap times from Friday practice did not give an accurate picture of the performance of the two cars.

Separating Hamilton from Verstappen on the timing sheets was Alpine’s Esteban Ocon and the second Mercedes of Valtteri Bottas.

Verstappen was only 0.068secs ahead of team-mate Sergio Perez.

But on the high-fuel race-simulation runs later in the session, the Red Bull was the faster car and Mercedes said they had work to do on the set-up.

Verstappen said: “We’re still learning and understanding a few things. Clearly the short run didn’t go to plan, lacking a bit of pace, but the long runs were quite a bit more competitive so of course that’s also important.”

Hamilton added: “It was OK. It has been a relatively decent day. I like the changes they’ve made to the track. It’s made it much more enjoyable and flowing and it’s obviously close between us all. Still a bit unknown but I am sure it’s going to be super-close.”

Both said they felt the changes to the track aimed at improving the racing were generally positive but Hamilton said that overtaking would be still be difficult.

“I tried following on my long run,” the world champion said. “I think it was Perez I was behind. It still wasn’t easy – still really wasn’t easy to follow – but I think it will be better than what we’ve seen in the past.”

Alpine’s Fernando Alonso was sixth quickest, ahead of Alpha Tauri’s Yuki Tsunoda, the Ferraris of Charles Leclerc and Carlos Sainz and the second Alpha Tauri of Pierre Gasly.

The session was brought to a slightly premature end when Kimi Raikkonen, in the final race of his career, crashed heavily at Turn 14.

The car was badly damaged but the veteran Finn was unhurt.

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