Leclerc leads opening practice from Perez

Leclerc, who has yet to finish an F1 or FIA Formula 2 race at Monaco, had to abort a couple of potentially even faster laps late on. But his 1m14.531s posted on medium tyres kept him at the top of the timing screens, despite the late improvement from Perez.

Defending champion and new points leader Max Verstappen, meanwhile, ran in fourth as the Mercedes contended with further porpoising trouble aboard the W13.

The first practice to take place in Monaco on a Friday during the modern era was typified by a breathless run of fastest laps from Max Verstappen and the Ferraris to that led to constant changing at the top of the leaderboard in the early part of the hour.

The leaders diverged with Verstappen sticking to the hardest available C3 compound, while the Ferraris opted for the yellow-walled C4 medium Pirellis.

Verstappen had been first out on track ahead of Alex Albon, George Russell, Sainz and Red Bull team-mate Perez.

The Dutch racer had complained of early DRS activation problems, like those that hobbled him in qualifying and the race last weekend in the Spanish Grand Prix.

But he was soon up to speed, as Daniel Ricciardo set the early benchmark with a 1m20.364s effort to lead Fernando Alonso and McLaren stablemate Lando Norris – still under the weather after his bout of tonsilitis in Spain.

Leclerc was the first driver to launch under the 1m20s, romping to a 1m17.993s before Sainz pounded round the principality seven tenths faster only moments later as the newly resurfaced track started to rubber in.

Then Verstappen commenced his initial stint on hard tyres, moving top with a 1m16.582s to sit clear by half a second.

As the field chased after the 1m10.166s lap record set by Lewis Hamilton in Q3 in 2019, Leclerc then ran fastest in all three sectors.

Verstappen fell just a tenth shy next time around, the RB18 completing the tour in 1m16.276s after 10 minutes.

While Hamilton and…