Felipe Massa topped the timesheets on the final day of the opening pre-season test, as Mercedes powered teams continue to dominate.
In the two-and-half-weeks before the cars next take to the test track, some teams can afford to award themselves a well-deserved slap on the back whilst others look set to be burning the midnight oil.
On a day that saw the previous mileage almost doubled, Nico Rosberg completed a full race distance while Fernando Alonso and Kevin Magnussen both completed over 100 laps.
Overnight rain which continued until late into the morning meant that wets were the order of the day as proceedings got underway, the teams finally switching to Inters around lunch time before the dry tyres emerged in the afternoon. That said, it remained damp throughout the day. Only one driver ran with the soft compound when conditions improved, Juncadella in the Force India, the rest opting for hards and mediums.
Williams continued with the programme it has run over the previous days, focussing on new component, systems and reliability checks. Massa completing 86 trouble-free laps on his way to posting a best time of 1:28.229.
"It wasn't a great day because it was raining," said the Brazilian, "but we completed some laps in the wet conditions which was interesting to understand how the car behaves in wet, with the tyres and new power unit.
"We managed to do many more laps today than we have in the last three days which is important," he continued. "Today we didn't have any issues with the car which I think is also another step forward. We now need to concentrate and prepare with an aim to do more laps per day in Bahrain.
"Overall, I'm happy with my first days with Williams and I'm pleased with what I have seen in the team this week. For sure it is important to be competitive, but testing is testing, and we now need to look to prepare for Bahrain and then towards the first race, which is the most important thing.
"It was a good day for us," added Rod Nelson, the Grove team's Chief Test & Support Engineer. "It was what we were hoping for earlier in the week but it was good to start getting more mileage in the end. We still would have liked to have done more laps but there were several red flags today which interrupted running so to hit 86 laps is still a good result.
"We are very happy with the performance and reliability of the car up to now. We still have a lot of work to do when we get to Bahrain and in the time leading up to then but overall, we are pleased with how we have ended the week here."
Second quickest was Massa's former teammate, Fernando Alonso, the Spaniard completing 115 laps, thereby bringing the Maranello outfit's total to 252 laps this week, equivalent to 693 miles.
Given the weather, the first part of the day centred on evaluating the wet tyres and on further work on management of the various procedures that are used on the new car. In the afternoon, the team was able to make some set-up adjustments to the F14 T.
"A busy and very demanding day," said Alonso, "during which we were able to do a good number of laps, which is the real aim of this first test. It's difficult to get a clear picture of the behaviour of the wet tyres because the track conditions were in between damp and dry, which is maybe the worst situation for understanding how the Intermediates perform.
"The afternoon went well and we tried various aerodynamic and mechanical configurations, gathering a lot of data that will prove useful to continue the development work of the car."
Another Spaniard finished third, Daniel Juncadella making his debut with Force India, one week after being confirmed as Test and Reserve driver. The youngster completed 81 laps on his way to posting a best time 1.228s slower than Massa, though it was on the soft compound.
"It was my first day working with the team and it was a big challenge because of the tricky conditions," he admitted. "I took things very cautiously because I had never driven a Formula One car in the wet and for the whole day the track still had damp patches. It was a case of building up my confidence and learning how the team operates. It was a great experience and I made sure to make the most of it.
"We covered a lot of laps, which was a big improvement after quite a frustrating day yesterday. It's what the team needed before the Bahrain test to really start understanding the car. I want to thank the team for today and I look forward to the rest of the season."
"The final day in Jerez has proved to be the most productive so far," added Otmar Szafnauer, the Silverstone-based outfit's Chief Operating Officer. "Despite the mixed weather conditions, Daniel was able to cover 81 laps, which has given him valuable experience for his role as a reserve driver this season. The car has run reliably all day, which is a result of all the hard work carried out earlier in the week to resolve some of the initial reliability concerns.
"During these early days it's paramount to get laps under our belt and over the last four days we have clocked up almost 650 km. It's not been an easy test operationally, with lots of different challenges, but the whole team has done an extremely professional job to ensure we maximised the test days we had available."