Spanish Grand Prix: All you need to know about Barcelona

The Spanish Grand Prix has so far been a chastening weekend for Ferrari - and for everyone else hoping for a championship battle that involves more than the two Mercedes drivers.

Ferrari threw a huge effort into improving for this race, in the attempt to close the gap on a team that might have scored four consecutive one-twos to start the season but still seemed tantalisingly within reach.

Ferrari not only brought the traditional aerodynamic upgrade to their car for the first European race of the season but also unusually introduced a new engine. Two races earlier than originally planned.

It smacked a little of desperation - the Circuit de Barcelona-Catalunya is not a track layout that particularly rewards extra engine power because of its corner-heavy design - but it also underlined their determination to finally get their season on track after a disappointing start.

But it has not worked out that way. Mercedes also brought an aero upgrade, and this one was bigger than Ferrari's - insiders say it was worth a huge 0.4 seconds a lap.

The result has been the biggest gap between Mercedes and Ferrari so far - Valtteri Bottas' pole position was a massive 0.866secs faster than the quickest Ferrari of Sebastian Vettel. With Lewis Hamilton in second place on the grid, a fifth consecutive silver one-two looks a strong possibility on Sunday.

It was all the more painful for Ferrari because Barcelona is the track where they had looked so strong in pre-season testing that Mercedes headed to the first race in Australia thinking they were behind.

Vettel said: "We started off well in the winter and coming here and being quite far behind is not nice. We have brought some updates and we did made a step forward but it looks like Mercedes have done a bigger step so not necessarily good news for us."

Bottas said: "I have to say that when I saw the times, definitely we expected Ferrari to be closer. Everything based on winter testing, this seemed to be a track that really suits them and since the practice, we saw yesterday that we were in good form.

Vettel, as ever, was talking positively about his hopes for the race, but the reality is that Ferrari were just as far off on race pace in Friday practice as they were over one lap in qualifying on Saturday. Even if Vettel can get ahead of a Mercedes at the start, on a track where overtaking is notoriously difficult, it's hard to see how he can win. The Mercedes is so much quicker that you'd imagine they would find a way by somehow.

Mercedes have problems of a different kind, with the focus of the season rapidly shifting from their expected but evaporating battle with Ferrari to the one between their two drivers.

This was Bottas' third consecutive pole position, and Hamilton was in the monosyllabic mood he often can be after being beaten by a man in the same car.

There were extenuating circumstances for his defeat, up to a point. He had pitted when coming across a yellow flag in second qualifying, aborting a flying lap. Which left him in the garage with an under-charged battery. Which meant he had to go out early for his first run in the top 10 shoot-out to charge it. Which put him in traffic for the start of his flying lap, which compromised it.

It was scruffy - wheelspin out of the final corner on to the straight at the start of it, running wide at Turns Eight, 11, 12 and bouncing over the kerbs at the chicane. "They just weren't very good laps," Hamilton said of his efforts in final qualifying. "Simple as that. And Valtteri was just quicker today and rightly deserved the pole."

As Hamilton admitted, Bottas has looked like the man all weekend and assuming he leads into the first corner, he will be tough to beat.

Last time out in Baku, Hamilton was a bit too soft with Bottas when disputing the first corner, and he made it clear both there after the race and here in Spain on Thursday that it would not happen again.

Team boss Toto Wolff, unsurprisingly, is nervous about the developing fight between the two of them. But he remains confident it will not deteriorate into the hate-fest that developed between Hamilton and former team-mate Nico Rosberg, which ended in incidents such as the crash that took both out on the first lap in Spain three years ago.

"It doesn't make us feel comfortable," Wolff said. "Everybody knows Turn One is very important in Barcelona - can be race-decisive. But the two have been so respectful with each other on and off track that we are in a very different place than we were in 2016.

"We completely acknowledge there is rivalry between the two of them and that rivalry will intensify the longer the championship goes if it is between them. This is something we must address in a transparent way.

"Like on any other given Sunday we will chat and talk about scenarios, play a few videos. They know. Lewis has been there and Valtteri has always been very open that he acknowledges the hard work that has been going on. He really respects the immense effort that has been going into the team's work so it is very different to 2016."