Nico Hulkenberg topped the timesheets on the first day of testing at Sakhir today whilst the Renault powered teams continue to experience problems.

Though nothing can really be read into the times at this early stage, the pace and reliability of the Force India, and its Mercedes power unit, is impressive, and appears to indicate that Hulkenberg's move back to the Silverstone-based team might not have been such a bad idea after all.

However, Red Bull's problems clearly continue, Sebastian Vettel not turning a wheel during the morning then stopping out on track, and bringing out the red flags, around ninety minutes after he finally did get going.

Repeating the pattern witnessed in Jerez, Mercedes appears to have the edge, the four German powered teams completing 238 laps (800.3 miles) between them, compared to 149 laps (501 miles) for the Ferrari teams and 95 laps (319 miles) for the Renault runners.

It was a perfect day for Hulkenberg who not only set the pace but set completed the third highest number of laps.

"A very positive and satisfying day," beamed the German. "We had a busy programme and we learned a lot. Time in the car is very valuable at the moment and so it feels good to cover so many laps and even complete two long runs at the end of the day. That gave me a chance to see how the car behaves and to start getting a feel for it, which was not something I was able to do in Jerez.

"It's great that we've already done some set-up work and started to improve the drivability of the car," he continued. "But it's still very early stages; we are learning with every lap and we face a very steep learning curve in the coming days."

"Our test has got off to a positive start," added Chief Operating Officer, Otmar Szafnauer. "79 laps is a good effort and it's just what we need at this early stage of the VJM07's development. The aero work this morning ran smoothly with the constant speed runs giving us some aero data we required. In the afternoon we started evaluating the soft and medium tyres, and running through different set-up options - changing ride heights and rebalancing the car. We ended the day with a couple of longer runs on the soft tyres."

Fernando Alonso was at the wheel of the F14 T as Ferrari resumed the programme it began in Jerez, working on further checking of all aspects of the new power unit systems and some aerodynamic testing. Today, particular attention was paid to fine tuning the new brake by wire system, to optimise the balance of the car.

"It's nice to be driving again," said the Spaniard who stopped on track twice over the course of the morning session, "especially when you have more reference points compared to the previous time, which means you get a better feeling for the car. We are also at a track that is more representative, with normal temperatures, where it's been easier to understand tyre behaviour. We are in a phase where we are discovering things and with every lap, we learn something new. For everyone, there is still a lot to do to be well prepared for Melbourne, so it will be important to make the most of every day we have available to us."

At Mercedes the focus was to optimise running on the hard tyre in temperatures more suited to race conditions. Lewis Hamilton completed two twenty-lap stints with the team taking a close look at tyre performance and car data. Unfortunately, a brake issue ended the programme slightly early, though the German team is confident this will be fixed in time for tomorrow when Nico Rosberg will be in the car.

"It's been impressive to see us start the Bahrain test with good mileage and reliability," said Hamilton, "especially when you see how difficult it is for everyone with the new regulations. The team can be very proud of this after so much hard work.

"Today was another good test of the car to see if any issues came up," he continued, "we had a small issue with the brakes at the end but were still able to achieve a lot of laps. We're not aiming to be top of the timesheets at the moment, it's more about ticking the reliability boxes, but we can be happy with where we are before the halfway point of the pre-season tests."

"We ran our programme as expected today until the running came to a conclusion slightly earlier than we would have liked with a brake issue," admitted Paddy Lowe. "We did get through all of the planned data logging runs and the lap count was high. There is a great deal still to be done and a lot of the things we've been focusing on during the break since Jerez are working as intended. That is a great credit to the team working on the car at the factory and at the track to carry on from where we left off at the last test. Nico will be in the car tomorrow and we look forward to doing more long runs in consistent weather conditions."

Kevin Magnussen and McLaren continue to impress, the Dane completing 81 laps - making him the second busiest driver today - on his way to posting the fourth best time.

Magnussen kicked off proceedings this morning by conducting a series of short aerodynamic evaluation runs, complete with monitoring equipment fitted to the car. In the afternoon, he completed a number of longer runs, aimed at putting mileage on the power unit and components, and also to proof theories and improvements introduced after the first test in Jerez earlier this month.