Vettel left scratching his head after Hamilton's Spain win

Lewis Hamilton left the Russian Grand Prix scratching his head, at a loss to explain why he had struggled all weekend with the balance and handling of the Mercedes.

The questions were posed to both the driver and the team, with Toto Wolff insisting there was “no silver bullet” required to rectify those issues.

In the space of just two weeks, Hamilton is back to winning ways, merely further paving the way for a rivalry for the ages with Sebastian Vettel.

Will it prove a three-way title race? At this stage perhaps it is too early to say but, despite Valtteri Bottas’ excellent race win during Hamilton’s season nadir in Sochi, it seems unavoidable that 2017 will be a title race dominated by Hamilton and Vettel.

In Spain, there was everything. First off was the wheel spin on the line followed by Vettel getting the jump on Hamilton.

Even more exquisite was the moment they appeared side by side post-pit stop, the pair banging wheels and Hamilton forced into the run-off area.

And in the final chapter of their latest head to head, Hamilton gained the upper hand, using DRS with aplomb to fly past Vettel and take a race win which had, at one stage, looked highly unlikely.

The pair were all smiles post-race, no suggestion between either that one was more at fault than the other in the wheel-banging episode. In fact, Hamilton went as far as to say, “it’s a real privilege to race against such an awesome driver”.

Trying to second guess who will come out on top in what looks likely to be a season-long duel is impossible to predict.

There is no doubting the capability of both men but their tussle is as much as an engineering race as one on track.

The Spanish Grand Prix was a pertinent case in point in that argument, Mercedes’ car, the W08, coming out with its first big upgrade of the season.

We’ll talk of the nuances of that change in a moment but arguably the key aspect was the fact that the upgrades – in Spain at least – made the Merc seem a lot kinder to the soft tyres than they had been.

Most watching thought that even when Hamilton scythed into the lead, the race could well end up being Vettel’s still, so kind have the Ferraris been on the softer rubber but Hamilton held firm with barely a quibble down the race radio about how the Pirellis were late on as he has done at past races.

So what has been behind the W08’s increase in pace? Most simplistically put, the car is lighter and, with less weight to carry around the track, is hence quicker. The general consensus is it has been about 6kgs overweight this season but that has been slimmed right down.

Much of that weight shedding has come from a revised gearbox while, in addition, the suspension has been overhauled both at the front and the rear, seemingly giving Hamilton’s car a far greater balance at the opening European race of the season.

While Mercedes went for one big upgrade – in part down to the complexities of the work on their gearbox – Ferrari have been chipping away in the development race all season long.

There were the front wings and new floor in Bahrain, while there were further aerodynamic alterations in Barcelona: slight tweaks to the front wing and bargeboards, with a shift in its T-wing, of which it was the front-runner.

What have all those changes meant? Well, one would argue on the outcome of this race that Mercedes are now quicker although Vettel had gremlins in the pits, Hamilton got the jump with his and strategically Merc were just that bit wiser.

So are Merc really quicker at this stage? To a certain degree, it’s a moot point but Vettel tellingly said to Daniel Ricciardo, the third man on the podium, “I was eight seconds ahead and then…I don’t know how we managed to lose that. I dunno.”

Vettel may be taking his turn to scratch his head but he has not once finished out of the top two this season and keeps his championship lead for six points.

It’s a rivalry finally balanced. Monaco in two weeks time cannot come soon enough.

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