Szafnauer believed his Enstone-based squad had been on the verge of signing Alonso to a fresh F1 contract as they neared the end of negotiations ahead of the summer break.
But despite being informed by Alonso on the Sunday night of the Hungarian Grand Prix that everything looked set to be sorted out by the lawyers, Szafnauer said he was shocked when he read Aston Martin’s announcement on Monday.
“It was the first confirmation I had,” he said, when asked by Autosport about how he discovered Alonso has done a deal with Aston Martin.
“Obviously, when we're in the paddock, there's all sorts of rumours, and I had heard rumours that Aston were interested.
“Once you hear that they're interested, there's probably discussions that took place and there's some other indications that discussions took place, like walking out of the same motorhome at the same time, all that kind of stuff, which I saw.
“But I was confident that, even with the discussions, and there's nothing wrong with exploring, that we were very close.
“So yes, the first confirmation I had was the press release. I did ask the question [to Alonso]. And I was told: 'No, no, I haven't signed anything.' So I was a bit surprised.”
Pushed on whether he had spoken to Alonso since the announcement was made, Szafnauer said: “I haven't talked to him, since he's on a boat, I think, in the Greek Isles somewhere.
“I took this morning to address the staff here in Enstone. And the second thing I'm doing is talking to you. And yesterday, I fielded a bunch of calls from other potential drivers.”
Szafnauer said that Alpine and Alonso had all but agreed a 1+1 contract extension, which would guarantee the Spaniard a seat for 2023 with then an option for 2024 and beyond.
It is understood that one of the elements that was central to Alonso’s future thoughts was on staying in F1 as long as possible, as he felt just a single year commitment was not enough.
Szafnauer said: “There were just a couple of minor points that were outstanding, as he said that his lawyer would get back to us on. I believed that to be the case.
“And then, before he left, I confirmed with him that we would be signing soon. And he said, 'Yeah, don't worry, I haven't signed with anybody else.'
“We'll continue this in the next couple of days.”
He added: “We offered a one plus one deal. And we discussed with Fernando that: 'look, if next year at this time, you're performing at the same level, of course, we will take you and that could have carried on'.
“But I think he wanted more certainty independent of performance: ‘I want to stay for longer.’ And I think that was the crux of the going one plus one as opposed to two plus one or three plus one or three years.”
