Red Bull

The drama of Jerez has declined into a crisis for the World Champions. Though the RB10 completed more laps this week than it managed in southern Spain, the results were nevertheless significantly more concerning and damaging for Red Bull's ambition of securing a fifth World Championship - as the team failed to fix their troublesome new charger.

What could have been dismissed as teething problems after Jerez now looks to be chronic. To what extent the blame lies with Renault and what extent it rests with Red Bull's reluctance to switch focus onto 2014 at the same time as Mercedes and Ferrari is a moot point. What is unarguable, however, is that a problem Christian Horner dismissed as "nothing major" now looks to be grievous. Indeed, the essential problem with the RB10 appears to be that the car is susceptible to so many - each of the many malfunctions the team encountered this week were new from Jerez.

"There's no question that Red Bull are in deep, deep trouble," says Sky Sports' Ted Kravitz. "They are finding that the more laps they do, the more problems they have."

And it's not as if they are doing many laps - to date, the RB10's longest stint on the road has amounted to a paltry twelve laps - or that their problems are occurring at the sharp end of performance evaluations: the Red Bull's fastest lap this week was six seconds shy of Mercedes'. The Red Bull appears to be the worst of both worlds: slow and unreliable.

Where do they go from here? After Jerez, Adrian Newey literally went back to his drawing board. After Bahrain, the team may have to do so metaphorically as well. The suggestion from a rival team that the World Champions will introduce a B-spec car for the Spanish GP in May is entirely feasible; the RB10 has all the hallmarks of being a dud.

Mercedes

If Christian Horner was taking a leaf out of Jose Mourinho's book in proclaiming Mercedes as title favourites, then Lewis Hamilton had him rumbled. "We are just focusing on ourselves," the 2008 title winner insisted after blitzing the field on Friday. "Generally every time we go to a test, one team will build up the focus on one team just to take the focus off themselves - everyone has done it, so it doesn't really mean anything to us."

As Hamilton suggested, arguably too much emphasis is placed on 'mind games' and certainly Paddy Lowe wasn't rising to the bait. In fact, Mercedes' technical boss found himself in agreement with Horner - for now at least. "The strongest teams out there are the Mercedes-powered teams," he said at the end of the week's running. When asked about the Australian GP itself, however, Lowe only went so far as saying that the Silver Arrows are "in contention to do very well in Melbourne".

You can understand both his confidence and reticence. The former is borne out by two test sessions which appear to place Mercedes in a class of their own. Anyone with half an eye on F1 knows that testing isn't about headline times, but Hamilton and Nico Rosberg have both set them, while they're also well clear in terms of mileage. The former have come as a consequence of the latter, with the team pushing so far ahead that they were able to undertake qualifying simulations in Bahrain - which, according to Rosberg, flatter them as their rivals haven't really done the same yet.

Another note of caution is sounded because although the W05's reliability appears unsurpassed, that doesn't mean it's bullet-proof; being a works team might give Mercedes a head start but F1's new power units contain three times as many parts as their predecessors and so glitches are to be expected. Add to that the array of uncertainties a race weekend can throw up and it's little wonder Lowe is not looking too far ahead. But in the here and now, pre-season testing is surely going better than they could have hoped for.

Ferrari

If, as widely suspected, the four Mercedes runners are currently out front, Ferrari still look to be the best of the rest with their smooth, even serene, progress in Jerez followed up by 286 laps in Bahrain. Any other definitive conclusion would require a deposit of guesswork and gut feel because, as the most heavily-scrutinised team in the field, Ferrari are also, understandably, typically the most guarded. Not giving much away is their tour de force and with Fernando Alonso's fastest lap of the test set on a used set of soft tyres they are clearly intent on playing their hand close to their chest.

Yet one prevailing observation from trackside is that, at least compared to the Mercedes and McLaren, the F14 T looks a handful. "There's a lot of torque in the car," noted Kimi Raikkonen after his car-wrecking crash in the final minutes of Day Four.

Lotus

Its first appearance on Wednesday morning aside, the E22 did not feature prominently last week - although that did not stop Technical Director Nick Chester labelling its debut as "encouraging". There were stoppages, but to paraphrase just about any team member asked to comment on a breakdown, "That's what testing's for". Lotus completed 111 laps in total, including 59 on the last day alone. That puts them on a par with Red Bull's best on a single day, despite the World Champions also having Jerez to sort their car. Little wonder, then, that Lotus think they could have the measure of their fellow Renault runners at the start of the season.

The Enstone team might have chosen to plough a lone furrow with the E22's appearance, but by the sounds of it, they have been more conservative in the crucial aspect of cooling - something which could stand them in good stead. Factor in a belief that problems they've had with Renault's V6 turbo should be played down, not to mention confidence in the car's performance, then maybe there are signs that Lotus's difficult winter is not now seeming quite so barren.

McLaren

"We know we're not the quickest right now," mused Jenson Button on Friday. It's an indication of the change in form and mood at McLaren that he only had Mercedes in mind when he making the assessment. After hitting rock bottom in 2013, McLaren appear on the rise again.

The MP4-29 has attracted envious glances ever since its launch and trackside observers reckon the car is on a par with the W05 for driveability. That's important for both of the team's two drivers - for Button because an undemanding car is essential if his driving style is to prosper and for Kevin Magnussen because the process of acclimatisation that every rookie in F1 must confront can only be swiftly overcome in a consistent and undemanding car.

Might the MP4-29 also prove a winning car? In time, yes. At present, however, the team appear intent on ensuring they can walk before they can run - an understandably cautious approach after 2013's nadir. The fastest laps of Magnussen and Button at Bahrain were both set on the supersofts and although the relative fuel loads are unknown, the fact Mercedes were still faster on the soft compound - 0.7 seconds slower than the supersofts, according to Pirelli - suggests that McLaren still have plenty of ground to recover. But first things first: their job this winter has been to lay down the foundation blocks upon which they can build a successful 2014. So far, so good.

Force India

Scratching the surface of Force India's week suggests that their programme became more problematic, although the drivetrain problems experienced by Sergio Perez on Saturday might serve as no more than a warning that the Mercedes whizz that swept Nico Hulkenberg to the fastest time on Day One still comes with an occasional bang.

With 213 laps across the four days, the Silverstone team lagged a little behind Mercedes, McLaren and Williams in mileage but they were still happy enough with their week's work - Hulkenberg in particular sounding buoyant - and managed to complete some long runs besides starting to push the performance envelope. Yet after just eight days on track, it's clear that bullet-proof reliability is still much too much to ask for, regardless of which power unit you're using.

Sauber

A lap count of 240 for the week suggests that reliability is not a pressing concern; in fact, the only major stoppage the Swiss team suffered came on Saturday, when a structural problem with the C33 necessitated repairs. Thus, Adrian Sutil was limited to just seven laps - which might be of concern to him as he seeks to understand the vagaries of this season's technical changes.

If a measure of a team's confidence in their car's reliability is a decision to start running qualifying simulations, then it appears that all is going to plan so far. Having said that, Sauber introduced upgrades in Bahrain and there was nothing in their times to suggest real performance. Might they be sandbagging? Perhaps, but if lasting the distance really is that important come Melbourne, then it follows that grid position won't be the be-all-and-end-all either.

Toro Rosso

Eight days into pre-season and Toro Rosso's lap of mileage is becoming acute. The STR9 has only been seen on track for 193 laps and the team are even openly admitting in their own press releases that they are in the mire. "Everyone knows we are facing major problems and we are not alone in that," concluded Jean-Eric Vergne on Saturday. Heaven only knows what rookie teenager Daniil Kvyat is thinking as he attempts to acclimatize to a sport that must feel even more alien than it did at the time of his appointment.

The team have offered little in the way of detail about their problems but, as with parent team Red Bull, it's believed that the packaging of their Renault-supplied ERS is the primary problem - a suspicion endorsed by the team's reference to 'working hard with its technical partners to try and solve its problems before Bahrain part two when there will be just one item on the Toro Rosso agenda: laps, more laps and then plenty more laps.

Williams

The new dark horses for 2014 - and perhaps rather more than that if, as oft-suspected, the new season proves to be a campaign decided by reliability rather than outright pace. Although the team's fastest time at Bahrain was four seconds adrift of Rosberg's table-topping 'qualy' run, the Williams has yet to be run in similar spec. The team have instead focused on honing their new charger into being a reliable long-distance runner - successfully, too, it seems, with the FW36 completing more laps than any other car this week and strategist Pat Symonds proudly noting afterwards that the Williams is still the only car in the field yet to trigger a red flag. Could the FW36 be the tortoise to Mercedes' W05 hare this season? If you fancy a flutter, check out the odds on a Williams finishing on the podium at Melbourne.

Marussia

Back to square one. Having only managed 30 laps in Jerez after their late arrival for the first test, the team's hopes of progression in the desert came to naught - and considerable frustration. With a mysterious IT failure followed by a fuel system irregularity and then an engine blow-up, the team completed less than 25 laps in total. By Saturday the drastic - but understandable - decision had been taken to start again from scratch, with Jules Bianchi's four laps on track amounting to a basic shakedown of the new parts flown in overnight. A vital four days awaits next week, as the team strive to finally put some significant miles on the board.

Caterham

If the test saw a re-enforcement of patterns up at the sharp end which started to appear in Jerez, then much the same was the case down in Renaultland, where Caterham once more showed Red Bull and the rest how to do it - 'it' being some serious laps with the CT04. The power unit couldn't quite last the full four days (an electrical problem intervened on Saturday) but Marcus Ericsson, Kamui Kobayashi and Robin Frijns were nevertheless all happy with their mileage - doubly so for Ericsson, who was able to qualify for his FIA Superlicence.

While they hope to unleash more performance in the final test, it's clear that lasting the distance represents their best chance of causing an upset in Melbourne - and don't Caterham know it. Moreover, they will also be keeping an eye on the progress - or lack of - by Marussia, who barely managed a tenth of their mileage total last week.

Fastest laps of Bahrain Test One

1. Nico Rosberg, Mercedes, 1:33.283, New Soft tyres, Day Four.

2. Lewis Hamilton, Mercedes, 1:34.263, New soft tyres, Day Three.

3. Kevin Magnussen, McLaren, 1:34.910, New supersoft tyres, Day Two.

4. Jenson Button, McLaren, 1:34.957, New soft tyres, Day Four.

5. Nico Hulkenberg, Force India, 1:36.445, New soft tyres, Day Two.

6. Fernando Alonso, Ferrari, 1:36.516, Used soft tyres, Day Two.

7. Kimi Raikkonen, Ferrari, 1:36.718, New soft tyres, Day Four.

8. Felipe Massa, Williams, 1:37.066, New soft tyres, Day Three.

9. Esteban Gutierrez, Sauber, 1:37.180, Unknown tyre compound, Day Three

10. Valtteri Bottas, Williams, 1:37.328, Unknown tyre compound, Day Two.