Carlos Sainz has led a Ferrari one-two in Practice 1 for the Formula 1 Australian Grand Prix at a new-look Albert Park.

Sainz set a 1:19.806s just before the second of two red flags in the hour-long session, which saw him finish up more than half a second clear of team-mate Charles Leclerc’s 1:20.377s.

Leclerc ended up hundredths of a second quicker than Sergio Perez, who was joined in the top four by fellow Red Bull Racing driver Max Verstappen.

McLaren’s Lando Norris had been fastest initially with a 1:25.009s on medium (C3) compound tyres and then a 1:23.066s next time through, already going faster than the Practice 1 benchmark of 2019.

Verstappen took over top spot in the 10th minute when he clocked a 1:21.625s on a soft-shod (C5) Car #1, after which Leclerc set a 1:21.929s on hards (C2) and Norris a 1:21.811s on his initial set of mediums.

Verstappen raised the bar further with a 1:21.140s early on his second run, and was first into the 20s when he lapped Albert Park in a time of 1:20.909s in the 20th minute.

A red flag was called in the 25th minute due to debris which had fallen off Perez’s Red Bull on the exit of Turn 14, the final corner of the track.

At that time of that stoppage, Verstappen and Norris were still top two, with Leclerc third on a 1:21.815s set on hards, Daniel Ricciardo (McLaren) fourth on a 1:21.850s on mediums, and Esteban Ocon (Alpine) fifth on a 1:22.131s on mediums.

Mercedes’ Lewis Hamilton sat 10th on a 1:22.961s on hards, and team-mate George Russell 16th on a 1:24.361s on softs.

When the session got underway again, Sainz jumped from eighth to second with a 1:21.249s on a Ferrari fitted with hard compound tyres, before Hamilton moved to fourth on a 1:21.760s on softs.

Almost as soon as he had done so, Sebastian Vettel took his Aston Martin to third with a 1:21.661s set on softs, before he was pipped by Yuki Tsunoda’s (AlphaTauri) 1:21.635s on softs.

Verstappen crept down to a 1:20.857s in the 34th minute, just before Leclerc went even faster again with a 1:20.825s, with both on softs.

The Dutchman reclaimed the ascendancy from the championship leader with a 1:20.625s two laps later, before Leclerc clocked a 1:20.377s and Sainz made it a Scuderia Ferrari one-two with a 1:20.325s in the 38th minute.

Sainz put more distance between himself and the field when he wheeled Car #55 to a 1:19.806s with just over a quarter of an hour remaining, on used softs.

A second red flag was called in the 46th minute when Vettel parked his Aston Martin on drivers’ right on the exit of the flip-flop due to an apparent engine issue, as evidenced by smoke coming out of the rear of Car #5.

At that point, behind the Ferraris and Verstappen, Norris was fourth on a 1:20.878s, Ocon fifth on a 1:21.004s, Hamilton sixth on a 1:21.027s, and Ricciardo seventh on a 1:21.155s.

The session resumed with 10 minutes to go and Sainz, who has switched to hards for his final run, kicked up the dust as he got loose off Turn 2.

Perez took up third in the final four minutes when he moved to a 1:20.399s in a #11 Red Bull Racing entry on soft tyres, and that was the last of the changes at the top end of the timing screen.

Leclerc, however, had a somewhat eventful end to his session.

The Monegasque had already run off at Turn 1 straight after a practice start with 20 minutes remaining, then squirrelled on the gravel when he ran wide at Turn 12 with the chequered flag out.

Behind the Ferraris and Red Bulls all-told was Norris in fifth, from Ocon, Hamilton, Ricciardo, and Fernando Alonso in ninth.

The latter was a late improver to a 1:21.229s on a set of softs, after an innocuous spin in his Alpine at Ascari with about 20 minutes to go.

Alfa Romeo Sauber’s Valtteri Bottas rounded out the top 10, with Russell 12th on a 1:21.457s and Vettel 13th.

For reference, the benchmark in the corresponding session three years ago, when F1 ran for the last time on the old Albert Park layout, was a 1:23.599s.

While Sainz was fastest, he is the subject of a post-session investigation into alleged impeding of Zhou Guanyu (Alfa Romeo Sauber) at Turn 13, in the period before the first red flag.

Practice 2 starts at 16:00 local time/AEST.

Results: Formula 1 Australian Grand Prix, Free Practice 1