F1 2018: Mercedes predict more swings in title race

The battle for 2018's F1's world title will continue to fluctuate on "marginal gains" after Lewis Hamilton wrestled back the championship lead for Mercedes, reckons Silver Arrows chief Toto Wolff.

Just a fortnight after Mercedes were left with questions to answer after a sobering defeat to Ferrari in Montreal, a previous stronghold for the team, F1's world champions bounced back in emphatic style at the French GP with the team claiming a hat-trick of pole, win (Hamilton) and fastest lap (Valtteri Bottas).

Mercedes brought their upgraded engine to France at the second attempt and were not headed in any session all weekend, a development they admit played a key role in their return to form.

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"I think what you saw in Montreal in comparison to Le Castellet is that marginal gains matter," said Wolff after the team's third win of the season.

"We fell back in Montreal because we couldn't bring the new power unit, and we were racing power unit number one for the seventh consecutive race, and the others introduced their upgrade. This certainly didn't help.

"We also constantly are learning on how to set the car up in the right way in combination with the tyres, and of course we also brought some upgrades to the car which was good to see coming together.

"And all these gains in their respective areas added to a solid step that we could materialise on each of the three days at Le Castellet."

The leadership of the world title race has changed hands three times in the last five races between Hamilton and Vettel, with neither contender yet opening a lead in excess of 17 points this season.

Hamilton is back ahead again, this time by 14 points, but Wolff warned: "It can swing so quickly.

"A DNF and the other guy winning makes it swing in the other direction. I don't expect this to change in whatsoever way.

"This is going to be the story of the season."

Hamilton will get a first chance to increase his lead in just a matter of days' time with the Austrian GP playing host to the second leg of F1's unprecedented triple header this weekend. Mercedes are unbeaten at the Red Bull Ring since the venue returned to the calendar four years ago, with Hamilton winning in 2016.

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