Ferrari may have been quickest in F1 winter testing but it is world champions Mercedes who appear to be in best shape ahead of the new Formula 1 season.

That's the somewhat paradoxical conclusion formed across eight days of intriguing and revealing action at the Circuit de Catalunya in Barcelona.

But while Mercedes appear to have maintained an edge over Ferrari, the gap between the teams remains the subject of fierce debate in the paddock - as does the whereabouts of Red Bull relative to F1's strongest teams in 2017.

Behind them, the battle in the midfield looks particularly close, but hopes of a sudden leap forward by McLaren following their switch to Renault power have floundered after a trouble-filled two weeks for the team, pockmarked by five separate on-track breakdowns.

So who set the pace at Barcelona?

As the chequered flag fell in Barcelona on Friday night, it was Ferrari who topped the timesheets courtesy of Sebastian Vettel's 1:17.182 lap on Day Seven. Set on the new-for-2018 hypersoft tyres, Vettel set his benchmark on a five-lap attack run which also included laps of 1:17.913 and 1:17.664. Team-mate Kimi Raikkonen was second-fastest, less than a tenth behind Vettel with a lap of 1:17.221 on the final day.

Red Bull's best time on the hypersofts - Daniel Ricciardo's lap of 1:18.047 - was nearly a second shy of Ferrari's, but Thursday's cooler temperatures were more conducive to fast times.

Mercedes opted not to use the hypersofts at all. As a result, their world champions' best time of the winter was Lewis Hamilton's lap of 1.18.400 on ultrasofts, 1.2 seconds adrift of Vettel's benchmark.

But the Ferrari was also quicker on ultrasofts than Mercedes courtesy of the 1:18.079 Vettel produced on Day Seven, four tenths up on Hamilton's ultrasoft best.

Mercedes only claimed the fastest time on the medium tyres, the hardest compound to be run over the whole two weeks.

But these were the outright lap times - and very possibly a trenchant example of why the fastest laps charts at testing can be hugely misleading.

Because by Friday night all the talk in the paddock was whether Mercedes hold a substantial advantage and if Red Bull, not Ferrari, are really the closest challengers to the Silver Arrows.

But could Mercedes be stronger than ever?

On the penultimate day at Barcelona, both Mercedes drivers completed full race simulations - and to ominous effect. Close reading of the charts found Valtteri Bottas around a second per lap faster than both Red Bull and Ferrari. However, another important caveat was to be found in the small print: Mercedes only ran on the mediums.

Bottas subsequently denied Mercedes were really one second clear but it was a reassuring question to answer. "Mercedes are going into this championship as very much the favourites," accepted Red Bull's Christian Horner.

The general demeanor around the leading teams told an interesting tale too.

Hamilton was relaxed and assured, describing the W09 as an "improvement" and telling reporters "last year's car was great but this car feels better". Red Bull also had a spring in their step. "I'm sure Mercedes are still the top dogs at the moment but I don't feel we are far off," said Ricciardo. "If we can keep finding a few more things we can be very good."

And Ferrari didn't really have much to say, leaving others to fill in the gaps. "Sebastian is not a good actor when he is unhappy," said one confidant of the Ferrari driver.

What about the rest?

McLaren talked a good game in Barcelona but until Fernando Alonso's very late burst on the final day the on-track narrative was unsettling. The MCL33's five breakdowns were five more than Mercedes and Ferrari combined. Regardless of their plea for calm, the team will be arriving in Australia critically short of mileage. Have they pushed too hard with their self-described "aggressive" car design?

By contrast, Renault, McLaren's new engine suppliers, enjoyed substantial mileage and consistently showed strong pace.

Haas showed up well in the timesheets even though Romain Grosjean and Kevin Magnussen both set their quickest laps on relatively-hard rubber after the team elected not to include the hypersofts in their allowance. In a closely-bunched midfield, Haas look the likeliest candidate to be tucked in behind Renault, the new 'best of the rest' favourites.

Force India will only run their 2018 package in full upon arrival in Australia and struggled to show any meaningful pace across the eight days. "Hopefully we don't have this car in Melbourne," Sergio Perez told Sky Sports.

Toro Rosso did better than expected, with the reliability of their Honda engine the chief factor in the defied expectations. But it should be noted the team used as many power units - three - as they will be allowed to run through the entirety of the 21-race season.

With a Williams driver finishing bottom of the timesheets on all four days of the second test, there was no escaping that the Grove outfit had a bad final week.

On track, the car looked skittish and the team admitted the FW41 struggled to generate heat into the softer tyres. Sergey Sirotkin also had a week to forget, and it was only after Robert Kubica voluntarily gave up his seat on the final day that the Russian rookie finally produced anything of note.

The team say they don't know where their stand but it would appear they will start the new season somewhere between seventh and ninth in the order.

Sauber, meanwhile, look set to begin the new campaign in a familiar position of backmarkers. The benefits of the team's recently-forged alliance with Alfa Romeo won't be felt for a while and their new car is a handful: between them, Charles Leclerc and Marcus Ericsson crashed out four times.

So what's the pecking order?

With the usual caveats about reduced running, unknown fuel loads, varied engine settings, different tyres, and contrasting performance targets, here's how we think the pecking order runs ahead of the new season:

* A clear top three of Red Bull, Ferrari and Mercedes with the world champions out in front but with their advantage perhaps greater in race trim than qualifying.

* Renault as the best of the rest, albeit amid concerns that the top three have moved further away from the chasing pack, although several team bosses denied that was the case on Friday night.

* McLaren as the wild card in the pack as a result of their unreliability but with the team still confident their chassis and engine package can deliver a profitable season once a happy compromise is achieved between the Renault unit and the MCL33's tight packaging.

* A closely-packed midfield, with Force India's position particularly ambiguous until they deliver their full 2018 package. Haas could well be fifth in the order while Williams look likely to start the season in the lower half of the midfield.

* Sauber cut adrift at the back but with respectable reliability and Leclerc a few tenths ahead of Ericsson.

Roll on March 23-25 when all the questions will be answered.

The fastest laps of winter testing per team Team Driver Date Tyre Time Ferrari Sebastian Vettel Day Seven Hypersofts 1:17.182 McLaren Fernando Alonso Day Eight Hypersofts 1:17.784 Red Bull Daniel Ricciardo Day Six Hypersofts 1:18.047 Renault Carlos Sainz Day Eight Hypersofts 1:18.092 Haas Kevin Magnussen Day Seven Supersofts 1:18.360 Toro Rosso Pierre Gasly Day Seven Hypersofts 1:18.363 Mercedes Lewis Hamilton Day Six Ultrasofts 1:18.400 Force India Esteban Ocon Day Eight Hypersofts 1:18.967 Sauber Charles Leclerc Day Eight Hypersofts 1:19.118 Williams Sergey Sirotkin Day Eight Softs 1:19.189

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