Alonso shocked F1's silly season last summer when he slid into the Aston seat left vacant by the retiring Sebastian Vettel, leaving Alpine scrambling to find a replacement as it also saw junior driver Oscar Piastri move to McLaren.
The 41-year-old has a history of making bold team decisions, often ending up at the wrong team at the wrong time, ever since claiming two world titles for Renault in 2004 and 2005.
It therefore raised eyebrows when Alonso traded fourth-placed Alpine for Aston Martin, which finished seventh last year.
After taking an impressive fifth place in qualifying for 2023's season opener, just six tenths from Red Bull's polesitter Max Verstappen, Alonso admitted going to Aston Martin was "just a bet", but one that might pay off spectacularly from the very first season.
"I don't know even what to say, because eight months ago the project was just a bet," he said.
"But now to be race one with a completely new car - which I think we need still to unlock a lot of potential - to be in the top five fighting with Ferrari, Mercedes, it seems a little bit unreal, but we take it for sure."
Alonso was bullish that Aston's strong pace at Sakhir was just the beginning as the AMR23 is still a "very basic car" in its launch specification, although he also wants to see how strong the car will be on the very different circuits of Jeddah and Melbourne.
"Sure, we need to wait for Jeddah, Australia, very different tracks, so I'm curious to see if we can keep this form in different circuits," he cautioned.
"But also on the other hand, the car that we have now is just a very basic car that we launched and we start the season with, this [is a] completely new concept on the car.
"There is a lot more to come in terms of development of this project, so I'm optimistic for that.
"This project has the motivation to always go for more, so there are good things coming for Aston Martin."
