Carlos Sainz swapped notes with Fernando Alonso after testing McLaren

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McLaren's new driver signing Carlos Sainz compared notes with former McLaren F1 driver Fernando Alonso after testing this year's McLaren car.

Sainz has joined the team following the departure of compatriot and good friend Alonso, who quit F1 at the end of the 2018 season following four unsuccessful seasons with McLaren. The team has been in a steady state of decline since its last victory in 2012 and will start the 2019 season with a new driver line-up and heavily-revised technical team.

Sainz's first day in McLaren overalls came at the end-of-season test in Abu Dhabi last month, but his first media commitment with the team was at the launch of the OnePlus 6T McLaren Edition smartphone on Tuesday. Speaking at the 'Salute to Speed' launch event at the team's factory in Woking, he said he exchanged voice notes on the handling of this year's MCL33 with Alonso but would speak in more depth at a later date.

"We've sent each other a couple of voice notes regarding the balance of the car in the test, how it compared to the Renault etc," Sainz said. "We [Alonso and I] haven't sat completely around a table and discussed the direction of the team or what's going to happen or where the team is going, but we've sent each other voice notes commenting on car balance, the things we like or don't like.

"That's all I can tell for the moment. I imagine I will see him in the next two weeks probably back in Spain and we will probably talk a bit more in detail then than a couple of voice notes."

McLaren struggled for performance throughout 2019 and Alonso failed to score points at the final six races of the year as the car slipped down the order. Asked if it was immediately clear where the MCL33 was lacking, Sainz said the differences with his 2018 Renault, which outscored the McLaren by 60 points over 21 rounds, were not as obvious as the results suggest.

"It was not immediately obvious, no," he added. "It is probably maybe half a second between the McLaren and the Renault in qualifying, you divide that half a second into 21 corners, and you get an idea of what we are talking about -- we are talking about nothing.

But Sainz says he was relieved to be met by an optimistic team at McLaren, having feared it would be demotivated by bad results.

"Probably in the back of mind I thought maybe I would find a team that wishes that its season is over and we go for next year. But actually I have found a team that is full of battery even in November/December. Full of will to go racing next year, and that is an immediately contagious thing.

"It gets really well through everyone in the team and through me, I was coming full of energy and full of batteries -- and it has made me come even more than I thought to Woking to make sure that I cover all the areas before we go racing next year."