While it remains to be seen how the pecking order really stands, Mercedes boss, Toto Wolff describes the battle with Red Bull as a "dog fight".

Though the German team appears to have made progress in terms of the instability issues that it suffered in testing, it is clear there is still work to be done.

While Valtteri Bottas was the quicker of the Mercedes pair in FP1, finishing 0.298s off Max Verstappen's pace, Lewis Hamilton lost out to the Dutchman and Lando Norris in the more representative second session, albeit still 0.235s off the pace of the leading RB16B.

"The night has fallen and the conditions haven't come towards us," Wolff told Sky Sports. "It's a real dog fight," he added.

"When you overlay the fastest laps and even the long runs, it's just so very close that every kilogram in fuel load can have a very big swing so we don't really know," he admitted. "We are definitely closer here than we were in testing but I wouldn't know where to position us versus Red Bull."

"We're definitively in the mix," insisted Bottas. "McLaren, they looked pretty strong today, Red Bull was as expected.

"I think we are there," he continued, "I don't think we're the fastest at the moment, but we're not far off and we have a clear target of where we want to be."

Asked about his claim in the closing moments of the second session that his car was "undriveable", he said: "The last long run we did was pretty inconsistent. I couldn't really put any laps together as the car was, as I said, undriveable at times.

"A bit puzzled," he added, "but it's Friday and that's why we practice. It felt better than it did in testing in terms of how the car was feeling - so that's good - but also it felt like we're not yet there in terms of car balance. The inconsistency in the balance and especially in the rear of the car was one big highlight.

"The main thing in my mind is we have plenty of work to do if we want to fight for the pole and the win," he admitted.

"I know we still have a hill to climb, but we're staying positive," added teammate Hamilton. "That's not great for us, being that the rear is as unstable as it is.

"For people watching at home trying to understand, when you approach a corner and the rear moves, you are trying to find that tipping point," he explained. "The tipping point used to be further away with more downforce on the car and now it falls away much quicker than normal.

"We thought Red Bull would be as fast as they are, if not faster," he concluded. "So we know they are leading at the moment. McLaren are looking great too and it's great to see them taking a step. It'll be interesting to see how their long runs are."

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