Mercedes driver Lewis Hamilton set the pace on the penultimate day of pre-season Formula 1 testing.
The world champion underlined the impression that Mercedes have a clear advantage by beating Williams's Felipe Massa despite using slower tyres.
Hamilton was 0.24secs faster than Massa, who edged Ferrari's Kimi Raikkonen by 0.014secs, using a tyre which is some 0.5-0.8secs slower a lap.
McLaren-Honda again had their running curtailed by a reliability problem.
Hamilton, who will not drive the car again until the first race of the season, said: "It wasn't a spectacular day. The track seemed to have lost some grip to the last two days so it wasn't the best in terms of feeling but we got some running done and I feel good in the car."
Reserve driver Kevin Magnussen, standing for Fernando Alonso as the Spaniard recovers from concussion sustained in a crash last Sunday, managed only 38 laps before an oil leak in the engine ended the team's day shortly after lunch.
The Dane was eighth fastest, 2.203secs off the pace, after a run on the soft tyre.
But despite the setback, Magnussen sounded optimistic about the team's chances afterwards.
"Great to be back in the car today," he said on Twitter. "The McLaren-Honda feels great! Plenty more to come from this one."
Racing director Eric Boullier said: "We won't be as ready for the Melbourne as we would like, but we will do our best."
Boullier added that "reliability is still a concern" and he said he expected the team to take until the fifth race of the season in Spain in May "to be more competitive".
The season starts with the Australian Grand Prix on 13-15 March - live coverage of the race is on 5 live and the Sport website and app, with highlights on BBC TV.
Final pre-season test. Day three, Circuit de Catalunya
1 Lewis Hamilton (GB) Mercedes 1:23.022
2 Felipe Massa (Brz) Williams-Mercedes 1:23.262
3 Kimi Raikkonen (Fin) Ferrari 1:23.276
4 Carlos Sainz (Spa) Toro Rosso-Renault 1:24.191
5 Romain Grosjean (Fra) Lotus-Mercedes 1:24.200
6 Marcus Ericsson (Swe) Sauber-Ferrari 1:24.477
7 Nico Hulkenberg (Ger) Force India-Mercedes 1:24.939
8 Kevin Magnussen (Den) McLaren-Honda 1:25.225
9 Daniel Ricciardo (Aus) Red Bull-Renault 1:25.742