Part of Aston's factory roster since 2014, winning two GTE Pro titles for the marque in the World Endurance Championship, Thiim will follow in the footsteps of his 1986 DTM title-winning father Kurt as he makes his series debut with Lamborghini outfit T3 Motorsport.
But the fulfilment of a 20-year-old dream for the Dane to join one of Europe's most prestigious championships, which switched from touring car regulations to GT3 cars for the 2021 season, wasn't a straightforward process.
Although he has previous for racing outside Aston Martin's stable - having contested the Nurburgring 24 Hours in a Phoenix Racing Audi last year - Thiim's path into one of the 29 seats on the bumper 2022 DTM grid had plenty of hurdles.
Originally, the plan was to get Aston Martin to return to the DTM for the first time since 2019, when R-Motorsport fielded a quartet of self-built Vantage Class One cars with a licence from the British manufacturer.
T3 Motorsport showed interest in running Aston machinery in the DTM after growing frustrated by a lack of support from Lamborghini during 2021, but an agreement could not be reached to switch cars over the winter.
Toksport, which has established itself in ADAC GT Masters with Luca Stolz, then entered into talks with both Mercedes and Aston Martin about competing in the DTM full-time in 2022 following its successful wildcard appearance last year in an AMG GT3.
However, with Aston Martin’s order book already at full capacity and with no other Vantage GT3s readily available at its Banbury base, it was simply not possible for Toksport to source a new car for this season.
Once it became clear that the Aston route was closed, Thiim’s manager Dennis Rostek tried to convince the sportscar maker to let him represent another marque in the DTM. Aston was initially hesitant, but green-lit the deal with T3 Motorsport in March.
"Initially, it was all about Aston Martin entering the DTM this year," said Rostek, who heads the Pole Promotion management company.
"I think that Aston Martin definitely belongs in this racing series, but no agreement could be reached. In the end they decided to strongly support two other racing series [GT World Challenge Europe and the Nurburgring-based NLS].
"I then started talking and asked for a release [from his contract]. At first they smiled wearily, [but] I didn't give up. We kept trying for so long."
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Thiim added: "The English are a bit stubborn, but everything went well.
"Jens [Feucht, T3 Motorsport boss] and Dennis lost their last few hairs because the negotiations were tough. But now we are here and I am super happy."
T3 Motorsport was interested in recruiting Thiim when it first joined the DTM in 2021, but the team eventually opted for Esteban Muth and Esmee Hawkey for its two-car line-up.
Muth left T3 Motorsport over the winter to join BMW squad Walkenhorst Motorsport, opening the path for Thiim.
The 32-year-old made sporadic race appearances in a variety of championships last year, but has now secured two full programmes for 2022, dovetailing his DTM commitments with a season in GTWCE’s Endurance Cup with the Prodrive-run Beechdean AMR team.
"Jens has always been ready because it was also his dream to do something together," said Thiim of his T3 collaboration.
"That's why I'm happy about Jens' trust, because the project got off the ground very late.
"We are clearly behind the others in terms of time, but we don't let that dampen our spirits and are still very motivated. And I'm sure it will be really good."
