Asked if he felt the team was set up to win at the time he made the switch to Ferrari, Sainz said: "Absolutely.
"I think I have said it a couple of times already that I feel like McLaren, as a race team, is ready to win championships. They just need a car capable of doing it.
"As was demonstrated in Monza, they had a car capable of taking a one-two and instead of getting nervous or collapsing, the race team, the engineers, the strategy, is so strong. What they did was to take a one-two, and with the fastest lap with the first opportunity they had.
"I know how strong that team is. Because of that, it’s a great reference for us at Ferrari to fight against them in the third-fourth championship because I feel like that team is ready to win races if a good car is given to the guys who are running it.
"It is an interesting challenge for us as a team. We can learn from it and take it on board for next year when we hopefully can have a chance."
McLaren to "keep battle alive" with Ferrari to the wire
For now, McLaren team principal Andreas Seidl is focused on this year's battle with Ferrari, one the Woking-based team leads by just 17.5 points going into the final seven races of the 22-grand prix campaign.
In a nip-and-tuck fight that is as important to both teams as the Mercedes-Red Bull duel for the titles, Seidl said: "We have a strong package.
"We need to make sure at every single weekend, together with Lando and Daniel, we maximise what we have and then I’m confident we have everything in our hands to keep this battle alive until Abu Dhabi.
“At the same time, I am fully clear it will be a very intense battle, and track dependent as well.
"We will have strong weekends and there will be weekends where Ferrari will be stronger, as we have seen throughout the season so far.
“Overall, we have the package to fight for this P3. We have the team and the drivers and that is what we are focusing on, independent of what other teams are doing.”
What do you think?
Seidl seems to have brought McLaren's Mojo back. The best thing that Zak Brown has done is employing Seidl, before that progress was incredibly slow and especially as Brown kept courting Alonso.
Even the lineup they now have is working for them. Norris is a huge talent, and Ricciardo unquestionably too.
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