Mercedes boss Toto Wolff says Lewis Hamilton is in the best physical and mental state he has seen, with the whole team "motivated" to stay ahead of the F1 pack and make history.

Hamilton hit the track in the world champions' new W10 car in the afternoon of 2019's opening test day at Barcelona as the team racked up over 100 laps on the challenger's official debut.

Wolff has been impressed with the five-time champion's fitness and mindset since returning from his winter break.

"The weight regulations have been lifted and he came back stronger and musclier than before," said Wolff.

"He's in a super mental state, the best I've seen so far. He looks physically and mentally in shape - half an hour before the session started he was all ready to go."

4:52 Craig Slater brings you the latest F1 news from the first pre-season test in Barcelona. Craig Slater brings you the latest F1 news from the first pre-season test in Barcelona.

That determination is reflected by the wider Mercedes team, according to Wolff, with the world champions chasing an unprecedented piece of history in 2019 - a sixth consecutive world championship double.

"It is very motivating. It wasn't done before but there's a reason why it wasn't done before, it's very difficult," said Wolff.

"It feels like you have 30 seconds left in the Super Bowl and you need to catch the ball. It's not trivial to catch the ball in the last pass and drag it over into touchdown.

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"So this is a little bit how it feels, but Ferrari is going to do everything to not let that happen and, equally, some of the other teams."

3:13 Mercedes' Lewis Hamilton and the Ferrari of Sebastian Vettel take to the track during the first day of testing in Barcelona. Mercedes' Lewis Hamilton and the Ferrari of Sebastian Vettel take to the track during the first day of testing in Barcelona.

Mercedes not timesheet watching

Not for the first time in recent years, it was Ferrari who made the early headlines on the testing timesheet on Day One as their new car completed the most laps and set the pace by over one second.

Wolff said Mercedes' perennial rivals already looked "ultra strong" but said his team wouldn't be distracted by what was going on elsewhere in the Barcelona pit lane.

"You need to be disciplined. We are all keen and looking at lap times and obviously you want to be quick and on the top of the leaderboard at every single session, but it's not the purpose of the test," he said.

"It's to go through all the parts, and look at what the data and sensors tell you.

"I've seen the time and the time was very quick, two seconds quicker than everybody else, and definitely the Ferrari has been going strong this morning."

Wolff added: "We don't know yet how the competitive order is going to be.

"We feel no sense of entitlement for being top of the pack and this morning shows you why."

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