Long-time Mercedes driver Marciello had been set to join Lamborghini and drive for the Iron Lynx team, which next year will debut the new SC63 LMDh in both the World Endurance Championship and the IMSA SportsCar Championship.
Now, Autosport sources have revealed, BMW has come in with a deal to lure him to race its M Hybrid V8 LMDh, which will compete in the WEC for the first time next year with WRT alongside a continued IMSA campaign undertaken by the Rahal team.
Marciello, 28, is believed to be one of the two drivers that Lamborghini talked about having in place to complete a six-strong LMDh line-up on the launch of the SC63 at the Goodwood Festival of Speed earlier this month.
Giorgio Sanna, boss of Lamborghini’s Squadra Corse motorsport department, said: “They are signed, but we will not communicate until the end of the season.”
He would only confirm that the additions to the squad would be new to Lamborghini and not drivers promoted from the GT3 ranks like Mirko Bortolotti and Andrea Caldarelli.
The Italians were the first drivers named by Lamborghini for the LMDh programme and have subsequently been joined by Romain Grosjean and Daniil Kyvat.
The likelihood is that Swiss-Italian Marciello has already signed a contract with Lamborghini for 2024, but that get-out clauses could allow BMW to steal him away, which looks increasingly likely to happen.
BMW has remained coy about if how it will expand its LMDh driver squad for 2024 when the M Hybrid V8 comes on stream in the WEC.
The German manufacturer is still evaluating whether it needs to bring in new drivers to bolster its 21-strong factory roster for the new season, BMW M Motorsport boss Andreas Roos stated earlier this month.
“What we are doing now as we get more and more calendars is to start the puzzle,” he told Autosport.
“You know how many championships you are doing and you see how many clashes there are, and out of this you see how many drivers you need.”
BMW has so far used seven of its factory contractees in the GTP class of the IMSA series with Rahal this year: full-season drivers Augusto Farfus, Philipp Eng, Nick Yelloly and Connor De Phillippi have been joined by Marco Wittmann, Sheldon van der Linde and Colton Herta across the rounds that make up the North American Endurance Cup.
Rene Rast and Dries Vanthoor, who both signed with BMW for 2023 after leaving Audi, appear certain to continue their long-standing relationships with WRT as it moves up to the Hypercar class of the WEC.
Marciello, a former member of Ferrari’s driver academy, has become hot property in sportscar racing after a prolonged stint as one of the star performers from the pool of Mercedes GT3 drivers.
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His credits since signing with the Stuttgart marque ahead of the 2018 season include winning the GT World Challenge Europe overall and Sprint Cup titles in his maiden season as a factory driver and the Endurance Cup segment of the series in 2022.
Marciello also triumphed at the GT World Cup at Macau in 2019 and claimed the ADAC GT Masters title last year driving the Mercedes-AMG GT3.
He is known to be be out of contact with Mercedes for next year after the completion of a second three-year deal.
Marciello has limited prototype experience: he had his first race in one at this year’s Daytona 24 Hours IMSA series opener in January with the High Class Racing LMP2 squad.
But his single-seater credentials include four Friday free practice appearances during a one-year stint as test driver for the Sauber Formula 1 team in 2015 while still on the books at Ferrari.
He also claimed the European Formula 3 Championship title in 2013 and was a race winner in GP2 in his debut season the year after.
