Daniel Ricciardo gave Red Bull a reason for optimism by topping both the lap times and the lap count on day two in Barcelona.
The Australian posted a 1:24.574 on the soft compound tyres just before lunch but after spending much of the first five days of pre-season focussing on shorter runs and aerodynamic tests, the three-time Grand Prix winner completed some longer stints in the afternoon ending the day with 141 laps on the board, a number only surpassed by Nico Rosberg in Jerez.
While Ricciardo's figures were impressive they were only just enough to stay ahead of much of the grid on what was the most productive day of testing so far in 2015.
Tight at the top
Kimi Raikkonen kept Ferrari's strong form going finishing second only being one hundredth slower than the RB11 on the same soft tyres and Felipe Massa made it three different engine suppliers in the top three and also three suppliers within one tenth of a second as the Brazilian set a 1:24.672 in the Mercedes-powered FW37.
Just 0.128 of a second behind Ricciardo was Sergio Perez in the 2014 Force India as the team conduct tyre tests which can then be used to help set-up the new VJM08 when it is ready to run.
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Hamilton sends a warning shot
Despite the very small margins between the top four on the times it was actually the man in fifth place who's best of the day was perhaps the most impressive or the most ominous.
Lewis Hamilton returned behind the wheel of the Mercedes W06 after having to call an end to his day on Thursday after just 11 laps through illness but given the afternoon to catch up, the world champion completed a stellar 89 laps setting a 1:24.923.
Why is that more impressive than Ricciardo? Well Hamilton's time was set on the medium compound tyre rather than the yellow-marked softs used by the Aussie. Then consider that with little change to the 2015-spec Pirelli's, to be just three tenths slower on a compound that last year was a full second slower than that the Red Bull used suggests Mercedes do still have a good advantage over a single lap.
Of course fuel loads and engine modes could distort the picture, with onlookers suggesting Ricciardo posted his time on quite a high fuel load, but given Mercedes have kept their cards close to their chest so far, this was the first hint of their performance.
In the morning Nico Rosberg overcame an inflamed nerve in his neck to complete a full race distance (66 laps) but perhaps understandably his pace was a little down on his team-mate.
McLaren progress but admit to worries
McLaren ran a restricted programme on Friday as an issue with the ERS on the Honda power unit on Thursday meant Fernando Alonso was likely running with the main 1.6L V6 without much electrical boost.
Despite the issues, however, the Woking team actually enjoyed one of its better days reliability-wise with a testing best of 59 laps - albeit the lowest on the day - and the seventh best time with a 1:25.961.
Bosses, however, admit testing is not going quite as they had hoped claiming the team have only done half of what they hoped to do so far.
Rest of the grid
Among the expected midfield teams GP2 champion Jolyon Palmer completed his first day of running as the Lotus reserve driver. The Briton managed 77 laps with a best of 1:26.2 in the E23.
Marcus Ericsson made his first Barcelona appearance for Sauber and the Swede continued to rack up the laps, as he did in Jerez, with 113 on Friday.
Bottom of the timings on day two was Carlos Sainz Jr. in the Toro Rosso, the Spaniard, however, was focussing more on track time as he prepares for his rookie season and 100 laps was another solid day for the Formula Renault 3.5 champion.
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