Lewis Hamilton headed an ultra-tight second practice session for the Spanish Grand Prix that featured five different cars within a quarter of a second at the head of the order.
Hamilton's lap, set slightly further into the hour-long session than the drivers he beat to top spot, was more than six tenths faster than the benchmark time in FP2 at Barcelona in 2023 and represented a gain of more than a second for Mercedes compared to last year's equivalent session.
His 1m13.264s included the fastest final sector of all and that ultimately dragged him to the fastest time by just 0.022s over Carlos Sainz's Ferrari.
FP1 pacesetter Lando Norris was third-fastest, a mere 0.033s further back, with Pierre Gasly an impressive fourth for Alpine ahead of championship leader Max Verstappen.
Verstappen - who conducted a test in Red Bull's 2022 car at Imola mid-week to offer a comparison as the team attempts to better understand its recent limitations - reported at the start of FP2 that his RB20 was still producing "this weird understeer mid-corner" and that it "doesn't bite".
He was ultimately 0.240s off Hamilton's time, though appeared in the mix with the McLarens and Sainz's Ferrari on the long-run simulations at the end of the session.
Verstappen was running the C2 medium tyres compared to the softer C3s used by Norris, McLaren team-mate Oscar Piastri - who was seventh-fastest behind Charles Leclerc - and Sainz.
Comparable long runs
Piastri (soft): 1m18.947s; 1m19.146s; 1m19.136s; 1m19.846s; 1m19.689s
Verstappen (medium): 1m19.434s; 1m19.421s; 1m19.719s; 1m19.511s; 1m19.614s
Sainz (soft): 1m20.276s; 1m19.801s; 1m19.944s; 1m19.851s; 1m20.171s
Norris (soft): 1m20.442s; 1m20.171s; 1m20.060s; 1m19.875s; 1m20.245s
*times set at start of long-run stints
Mercedes drivers Hamilton and George Russell - eighth in the FP2 order in the second W15 - were lapping in the high-1m19s and low-1m20s on their initial long-run laps.
Alpine drivers Gasly and team-mate Esteban Ocon expressed some pessimism on Thursday about their prospects at Barcelona, with no upgrades expected until just before the summer break at the earliest.
That prediction was shared too by team principal Bruno Famin even after Ocon had gone eighth in FP1.
But Alpine ended the day with both cars inside the top 10, with Gasly's standout effort backed up by Ocon setting the ninth-fastest time.
He was three tenths behind his team-mate, with the top 10 completed by Valtteri Bottas (Sauber).
Sergio Perez conducted a second stint on mediums at the start of the session and spent some time in the Red Bull garage after that before finally attempting a qualifying simulation run with a little over 20 minutes left on the clock.
But even then he was only 13th-fastest, 0.817s off the pace. He slotted in behind Haas pair Kevin Magnussen and Nico Hulkenberg and one hundredth ahead of Fernando Alonso as Aston Martin appeared to struggle.
The RBs were also an underwhelming 15th and 16th, with Yuki Tsunoda - marginally faster than team-mate Daniel Ricciardo - complaining on his long run that the car's "front under rotation sucks".
The Williams cars that were first to switch to softs were slowest of all in FP2.
Alex Albon was 19th and 1.543s off the pace - four tenths off Lance Stroll, next slowest in the second Aston Martin - with Williams team-mate Logan Sargeant two and half tenths further back at the end of his first day back to running the same specification as Albon.
