Leclerc started the day by running into the back of Lance Stroll’s Aston Martin, after the Canadian veered into the Ferrari’s path while on a slow lap.
That damaged the Ferrari’s front wing, but Leclerc was able to continue. Stroll, though, took no further part in the session because of rear suspension damage and the need to change his gearbox.
The Canadian was given a one-place grid penalty for his lack of awareness.
Leclerc said: “I have been feeling pretty good with the car. It hasn’t started the way I wanted with the crash with Lance, but after that it has been pretty smooth and I am happy overall with the car.
“The one-lap pace was strong. Whatever compound we were on, I was feeling quite comfortable and the lap time was coming pretty quickly. This is always a good sign.
“Qualifying is going to be fundamental and we have to be starting in front if we want to have a good result.”
Piastri ended up second despite his crash early in the session, when he went nose-first into the barrier at the first corner, Sainte Devote, but escaped with just a broken front wing.
Hamilton was 0.105secs off Leclerc on an encouraging day for the Italian team.
Piastri said: “The whole day has been a bit up and down. When we get everything together the pace is quite good, just not proving that easy to do at the moment. Some things to look at.
“Especially for myself it has been a messy day. Reset for tomorrow because the pace in the car is there.
“Ferrari are looking a lot stronger here than they have done. Today it has been more on my side that’s been quite messy. Plenty to learn and I think tomorrow will be an interesting day.”
Hamilton said: “The coolest track ever to drive. The most fun. Every year it is such a blast. It doesn’t matter what car you’re in.
“Of course it helps when you’re in a car that feels good and is quick. But with the grip, the speeds, it’s narrow, it’s fast, it’s the best rollercoaster ride of the year and it’s such a privilege.
“This morning I texted Ellen, who has been my assistant for 20 years, and said I can’t believe I am still so lucky to be able to do this every year and I was so excited for the day.
“It went smoothly. P1 was a little bit of a challenge, traffic and everything. P2 was much better. Got a little bit of time to find, Charles is very quick, but otherwise a good session.”
