Daniel Ricciardo says the unexpected news of Sebastian Vettel's exit from Ferrari at the end of 2020 compelled him to sign with McLaren without further due last month.
Vettel's scheduled departure from the Scuderia set in motion Carlos Sainz's move to Maranello which in turn triggered Ricciardo's decision to leave Renault at the end of his lucrative two-year deal with the French outfit.
The Aussie's move surprised many as the changes have taken place before this year's truncated season has started.
But Ricciardo believes that waiting to gauge McLaren's form this season before committing to the papaya squad could have jeopardized the opportunity.
"I think obviously Vettel’s announcement or news with Ferrari kind of sparked everything," he said on the latest F1 Nation podcast.
"And then things were moving pretty quickly around Carlos and all the other stuff.
"Although it seemed like there was maybe still time, I don’t actually think there was, to make movement – if that was what you were going for.
"This is all just what I’m playing in my head – if you start racing in July, which even then wasn’t 100%, but which we are by the looks of it, you’re not going to find out in the first race or the second race.
"You’re probably going to wait until August or maybe September until you really know where everyone’s at, and then I think it felt like it was going to be too late to get something you were after."
Ricciardo, who revealed that he had also been on Ferrari's radar from 2021, admits that this year's disrupted campaign forced him to rely entirely on McLaren's pitch and sales talks rather than on hard facts to assess his prospects for next season.
"The reality is you get pitches from whichever team is talking to you, and to some extent, especially now without having any races and any kind of proof other than last year, you have to go on what pitch excites you more than the other," he explained.
"If I go back to last year, which is our best reference for now, they were the team that made the most noise.
"Mercedes won the championship again, but it was quite clear to most that McLaren was the team which made the biggest step out of all.
"That was really encouraging for them, and that’s really all you can base it on.
"And then the pitch for the future, obviously they are switching power units and all that.
"Even talking about it now it’s certainly tough, because by no means was it an easy decision, and not having very much to gauge from 2020, that was pretty difficult."
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