Felipe Nasr continued Sauber's strong start to pre-season testing as he topped the timing on day three at Jerez.
The Brazilian rookie posted a 1:21.545 midway through the afternoon on the soft compound tyres to lead Ferrari's Kimi Raikkonen and Mercedes' Nico Rosberg as the only three men sub 1:22.
Felipe Massa was fourth quickest just seven tenths shy of the Sauber on what was a closely bunched timing screen among those who had relatively trouble free day's in Spain.
Indeed 1.6 seconds was the gap from Nasr at the top to Carlos Sainz Jr. in sixth but for two other teams things didn't go quite so well.
McLaren better but still lagging
It was a day of two halves for McLaren and Fernando Alonso as the Spaniard spent the morning complete the first decent mileage we have seen from the Honda-powered MP4-30.
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However, a water pressure problem meant the team could not run in the afternoon as the complexity of the new power units meant changing the faulty part would take several hours.
Based on last year's test, which is roughly where Honda are comparative to their rivals, 32 laps was a solid morning's work and the overall impression with the new power unit working as it should was positive.
Though lap times are irrelevant, and particularly given the circuit was still damp late in the morning, Alonso's best time of 1:35.533 was 14 seconds off the pace but at the time, given the conditions, that time was comparable to the other cars on track.
Renault problems hamper Red Bull
While McLaren cope with an all-new power unit, Red Bull also struggled with the 2015-specification Renault V6 turbo hybrid on Tuesday.
Daniel Ricciardo lost much of the morning and the early afternoon as the team changed the power unit and only a late flurry of laps kept Red Bull looking reasonable compared to their rivals.
Its not unexpected that Red Bull are perhaps having more trouble than most teams with an all-new car as their designs are famous for being all about aerodynamics and less about protecting what's under the bodywork
But having lost track time when Daniil Kvyat broke the only RB11 front wing the team had on Monday and only managing 48 laps on Tuesday they will be hoping the Russian can make up for lost time on Wednesday.
Rosberg leads impressive lap total
In the more important precedent as to how each team is looking heading into a new season, it was an impressive day on the lap tallies as all three 2014 engine suppliers had a car surpass the 100-lap mark.
After his 157 laps from Sunday, Nico Rosberg again led the lap count with an incredible 151 on day three leaving Mercedes just one lap shy of 400 in the opening three days of testing.
That came despite causing a brief red flag early in the afternoon as the engine shut down in the W06 but overall, reliability remains incredibly strong.
Only 15 laps behind him was Carlos Sainz Jr. in the Renault-powered Toro Rosso as the Spaniard had what is a perfect day for a rookie getting over two race distances under his belt and setting a respectable 1:23.187 in the process.
Finally Ferrari were represented by pacesetter Felipe Nasr who managed 108 trips around the near five-kilometre circuit for Sauber, though Kimi Raikkonen wasn't too far behind himself with 93 laps in the Prancing Horse.
Lotus too only fell four shy of the century with Pastor Maldonado which was particularly impressive after the team missed out on the first few hours with a telemetry problem.
Strong reliability = competitive season
Certainly the tallies are even more impressive on just the third day of pre-season testing, mechanics and engineers will still be learning the nuances and ironing out the glitches that are common with new cars but with reliability strong across the board, it will make for a very competitive season.
On the final day on Wednesday its about more of the same, as teams look to collect as much data as possible to take back to their factories in preparation for the second test in Barcelona later this month.