Alonso is one of several drivers in the running for Hamilton's Mercedes seat, with Villeneuve suggesting the Brackley-based team will want to stick with experience alongside George Russell in the short term.
“Yes, I'm amazed. Above all due to the timing. An announcement like this is now something never seen before, he told Gazzetta.
"Very strange. It will be talked about all year and it will be fun.
“The feeling is that Mercedes is missing something, and I don't think it will get back on its feet in two years. So Lewis is right to go to Ferrari. Where if he wins it will be fantastic, it will be the best it can be.
“Alonso would be great," the 1997 champion said while switching his attention to who might replace Hamilton.
"Also because you can't put another young player with Russell. Not at Mercedes.
"Toto [Wolff] will have the same ideas as him. He's like [Alonso's former boss at Renault, Flavio] Briatore: he has his own drivers, first he places them around, and then if anything he brings them into the team."
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