A former member of Ferrari’s Formula 1 driver development programme, Marciello has gone on to win some of the biggest prizes in GT racing since his switch from single-seaters in 2017.
He claimed the 2018 Blancpain GT Sprint Cup and overall titles, and won the FIA GT World Cup in Macau the following year.
The 27-year-old is currently running a dual campaign in GT World Challenge Europe and ADAC GT Masters, and is a regular part of the AMG driver roster in the major endurance races at Dubai, Daytona and the Nurburgring Nordschleife.
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But despite the DTM carrying more prestige than other GT3 championships thanks to its rich history and a top-class line-up of drivers who don't have to share their cars, Marciello says he doesn't find the category especially appealing.
“DTM was never a goal,” he told Autosport’s German language sister title Motorsport-Total.com.
“It's a GT3 series, like there are so many. If [Mercedes] AMG tells me to drive in the DTM, I will do it. If not, I won't.
“It's a series like the others, just with a bit more media exposure.
“My goal is to win everywhere I race, but it wouldn't be a step forward in my career if I drove DTM. This is the same car I drive here [in the GT Masters].”
A switch to the DTM for Marciello was mooted at the start of the year when Mercedes expanded its factory-supported fleet to eight cars, but those plans were eventually scrapped on cost grounds.
“I therefore preferred to drive in the ADAC GT Masters and with Timur [Boguslawski] in the GT World Challenge,” said Marciello.
However, the Italian hasn’t ruled out competing in the DTM in the future, saying he would be more than happy to race in the championship if Mercedes places him at one of its factory-supported teams in 2023.
“Next year we'll see,” he said. “As I said before: It's not my decision, it's Mercedes-AMG's.
“If they say I should drive DTM, then I'll drive DTM. I'll definitely do my best, just like I do every time I get in the car."
Marciello raced on the DTM support bill in the now-defunct European F3 series between 2012-13, winning the championship in his second season with single-seater powerhouse Prema as a Ferrari junior.
The 27-year-old is rated highly by DTM boss Gerhard Berger, who was previously quoted as saying that Marciello is “a really fast guy” and that he’d like to see him competing in the championship in the near future.
When Berger’s words were put to him, Marciello said: “I've known Gerhard since my time in Formula 3. Of course, I feel honoured.
“Gerhard has done a lot for the sport. For sure he knows who is a good or bad driver.”
