Leclerc was just six thousandths faster than Sergio Perez as the Red Bull Racing driver had a promising day at a venue he’s won twice.
It was a competitive session with Lewis Hamilton just 0.066s off Leclerc’s pace.
Oscar Piastri was fifth fastest at the end of the hour with Daniel Ricciardo 16th for RB.
Aboard his repaired Ferrari, Leclerc was unhappy with his car in the early moments.
Initially, he complained of heavy steering when turning left before suggesting the car was bent.
He was still third fastest in the opening 10 minutes, the pit wall unable to identify the reason for his concerns.
Told to carry on, Leclerc pulled rank and returned to the garage with 50 minutes remaining, complaining it was “impossible” the problem wasn’t evident on the data.
Carlos Sainz in the other Ferrari proved rapid; close to the top of the timesheets in the early moments before going fastest on the medium tyres after 15 minutes.
He then went on with it on the soft tyres to top the session, only being bumped by Perez as the Red Bull Racing driver completed his qualifying run.
Once Leclerc’s car was straightened out, he shot to the top of the timesheets.
His lap, a 1:43.484s, was only marginally faster than Perez and came with 13 minutes to run – later than his rivals had run meaning it wasn’t directly comparable with everyone else.
Having been fastest in opening practice, Max Verstappen was again rapid as the second hour of running began.
He used the medium tyres to log a 1:45.563s, a time nearly identical to his qualifying simulation from earlier in the day, such was the track evolution.
The Dutchman made a mistake at Turn 5, skating long but stopping just short of the barrier at the left-hander.
He’d been on a session-best lap to that point, though remained on the medium tyres used since the start of Free Practice 2.
Even allowing for the mistake, the Red Bull Racing showed promising pace in both cars, Perez four-tenths faster than the pack when he set his soft tyre lap after 35-minutes.
A power unit problem for George Russell kept the Brit in the garage initially as the team performed a precautionary engine change.
There were no such dramas for Hamilton, who was on track in the early minutes but complaining of a hot seat in his Mercedes.
He remained rapid, all but matching Perez’s single-lap pace during the middle part of the session.
Team-mate Russell did get out, running a set of hard compound tyres initially before swapping onto the softs in the final 10 minutes.
He didn’t set an especially blistering time, his 1:44.536s only good enough for ninth fastest, a full second off the one lap pace.
His session was then cut two minutes short when he was called back into the pits as the team detected an issue with the Mercedes.
Having kept its powder comparatively dry through the opening 25 minutes of the session, Lando Norris was only seventh on the timesheets as he began his qualifying simulation run, two places up from Oscar Piastri.
Norris’ attempt was ruined by Pierre Gasly, who awkwardly moved aside as they navigated the kinks on the front straight, quickly reporting a problem with his battery.
Abandoning the lap, and not completing another performance run, Norris ended the session out of position.
Piastri had a cleaner session and recorded a 1:43.950s on the soft tyres.
That left him only 0.033s slower than Sainz after 35 minutes, ultimately falling to fifth and half a second off the outright pace.
Ricciardo fell to 16th on the timesheets, 1.5s away from Leclerc and four-tenths away from his RB team-mate Yuki Tsunoda, who was 11th.
Franco Colapinto bounced back well after crashing in Free Practice 1 to all but match team-mate Alex Albon, while Oliver Bearman was 10th best for Haas.
With Nico Hulkenberg eight, and a promising showing that left the pair on the verge of the top 10 in Free Practice 1, it pointed to a promising weekend for the American-registered operation.