Michael Andretti's plan to enter F1 in 2024 -- revealed after his father, racing legend and 1978 F1 champion Mario, tweeted about it at the weekend -- certainly caused a stir in the motor racing world.
There is already an American F1 team, Haas, but the team has shied away from signing an American driver since it joined the grid in 2016.
According to Mario Andretti in an interview with Racer, Michael would "definitely" enter with an American at the helm of one of his cars.
What do we know of the entry at this stage?
Not a great deal, other than it exists only on paper and in the mind of Michael Andretti.
The FIA has cooled speculation around Andretti F1 by saying it is "not in a position to consider new entries" at this stage, but it seems unlikely F1 would completely shut off the prospect of another American team joining the grid right now.
The U.S. Grand Prix at Austin's Circuit of the Americas has just extended to 2026, the Miami Grand Prix debuts this year with the first race in a ten year deal and it looks increasingly likely a Las Vegas Grand Prix will be on the 2023 schedule. F1's business in America is booming.
So ... who are the likely candidates?
The obvious picks
If you were to put money on which American driver would race for an Andretti F1 team, 21-year-old Colton Herta would be the logical bet.
Herta, the son of IndyCar team owner Bryan, is the series' youngest race winner. He is clearly viewed favourably by the Andretti family -- Mario has compared Herta to the younger versions of Max Verstappen and Sebastian Vettel.
"The kid is for real," Andretti told Racer. "I know what I'm talking about, I know when I see something.
"I said the same thing about Max when I first saw him. I said the same thing about Sebastian Vettel when he won Monza with Toro Rosso and things like that -- I've been around long enough to see these things and I haven't been wrong yet!"
Herta also had a ringing endorsement from two-time champion Fernando Alonso ahead of last year's U.S. Grand Prix.
"I think he's a very good driver, very talented ... He would be a good fit for Formula One for sure."
Herta is the most exciting young American driver to come through IndyCar in a while. With a potential Andretti entry on the horizon he seems to be emerging at exactly the right time, although he will surely need to gain some kind of F1 experience through Friday appearances or test sessions in the near future.
Keep an eye on his form in IndyCar this year. A championship win in that series might mean he doesn't need to rely on Andretti for an F1 opportunity.
Alexander Rossi is the last American to compete in an F1 race, doing so at the 2015 Brazilian Grand Prix for Manor.
Were money not such a big factor in F1, Rossi might well have competed in more than just five F1 races. He moved to Europe as a youngster to advance through the junior racing pyramid below F1 but his opportunity was fleeting and, after a handful of races for Manor in 2014 and 2015, he was dropped ahead of the following season for the well-funded Rio Haryanto.
As it turned out, Rossi made the best of a bad situation. He joined IndyCar and went on to win the Indy 500 as a rookie with Michael Andretti's team. He's since established himself as one of IndyCar's best drivers and finished runner-up in 2018 and third in 2019.
He would clearly be a desirable pick for any team boss looking to start an American F1 team from the ground up. A bigger question would be whether Rossi would consider a return to F1. The Californian, who turns 31 this year, is well settled in IndyCar and told ESPN in 2020 he has no burning desire to return F1.
However, the lure of joining with an American team led by Andretti might be enough to convince him to give it a second shot, especially if Rossi has claimed that elusive IndyCar title before then.
Also, F1 hopes its new 2022 car, the cost cap and the sliding development scale it has introduced in recent seasons will bring the competitive order closer together, which could be a tantalising prospect for a driver who only ever competed in F1 for a backmarking team.
Josef Newgarden certainly looks like he should be an F1 driver. A two-time IndyCar champion, Newgarden has been one of the series' best drivers for a while. His name was always the one floated around in the media as a potential Haas F1 driver, but ESPN understands there have never been serious talks between the two.
Sadly, the window for Newgarden making the switch to F1 seems to have come and gone. Newgarden's age (he turned 31 in December) and his lack of F1 experience might count against him, given that we are talking about a potential 2024 entry.
A dark horse
Sargeant, 21, does not have quite the name recognition of the three drivers above him in this list but has some more obvious qualities which would make him a contender.
First off, he's part of the Williams F1 driver academy and, unlike Herta, competes in the junior ladder below F1. His link with Williams means he has immediate access to potential Friday practice appearances this season -- F1's races in Miami, in Sargeant's home state of Florida, and Austin this year seem like obvious places that could happen.
Secondly, Sargeant will compete in the 2022 Formula 2 championship with Carlin.
If you're not familiar with Trevor Carlin's team, you'll be familiar with some of its graduates to F1. Carlin has an amazing track record of producing F1-ready talent.
The list of drivers to have passed through Carlin on their way to F1 include Sebastian Vettel, Daniel Ricciardo, Lando Norris, Carlos Sainz, Kevin Magnussen, Jean-Eric Vergne and Takuma Sato.
Racing in F2 gives young drivers a chance to compete with tyres similar to F1, on the circuits the main series also races on. In two years, Sargeant could be better prepared for F1 than Herta and if he can perform in F2 it's not far-fetched to suggest he could be on that list of Carlin graduates before long.
Williams might well have something to say about it, but joining F1 with Andretti would be a match made in heaven.
Obvious candidates beyond those four are hard to find.
American driver Santino Ferrucci, 23, used to be closely linked to F1 as Haas reserve driver in 2017 and 2018, but he was not retained beyond then. Ferrucci's career seems to be a case of too much, too soon, as there were questions about his maturity when he was in the F1 paddock.
He was a controversial figure during his time with Haas, to say the least, earning himself a multiple race ban in F2 for a deliberate collision with Trident teammate Arjun Maini, who also happened to be a fellow Haas development driver at the time.
Ferrucci, labelled 'The Great Santino' in a 2010 GQ interview when he was just an 11-year-old karting sensation, has had mixed results in IndyCar and has seemingly drifted completely out of F1 reckoning at this point.