Nico Rosberg was quickest in P2 as Mercedes remained on top—but it was a close-run thing.
The Ferrari of Kimi Raikkonen was just 0.035 seconds behind.
Qualifying and race simulations were the focus of this session, giving us an early idea of the pecking order.
Mercedes were quick with both low and high fuel, and there's no question they remain the team to beat. But they don't look as far ahead as they were in Australia, and there was evidence they may struggle with tyre wear on longer runs.
Ferrari appear to have made substantial strides after a weak showing in Australia. Both drivers were quick over a single lap, and their "race pace" was only a shade down on Mercedes.
Also pushing at the front were the Red Bulls. Though a bit slower on the straights, the car looked incredibly good through the corner-heavy middle sector.
Their lap times on long runs were only around half a second down on the Mercedes.
McLaren and Williams are perhaps a little bit behind the leading three, and will be disappointed they seem to have dropped back. But the weekend is young, and they can't be ruled out at this stage.
Further down the grid, Lotus continued their disastrous start to the season. Romain Grosjean got stuck in gear after nine laps, and Pastor Maldonado didn't leave the pits at all.
Grosjean managed to get going again, but stopped again a few laps later. It was widely known Lotus were in trouble, but it's worrying that they still have such fundamental issues with the car.
Caterham looked little better. Kamui Kobayashi joined Maldonado as a spectator, with Marcus Ericsson comfortably slowest of the drivers who completed a lap.
Toro Rosso and Force India seem fairly equal, with Sauber a few tenths back.
Away from the track, Bernie Ecclestone was present in the pit lane, hearing the cars in the flesh for the first time in 2014. He told Sky Sports F1's live coverage that he thought the cars were a bit louder than he'd expected, but he'd still like to get the sound levels up a little.
Unfortunately for him, that's easier said than done.
Full session times from Formula1.com: