After retiring from racing at the end of last season, former Audi and BMW DTM racer Tomczyk was personally recruited by Berger to head up the promotion of its GT4-based DTM Trophy support series with the job title of DTM Representative Brand & Sports.
He has now taken on greater responsibility for "the sporting direction of the DTM platform" after what's been described as an internal restructure, which means he has taken on some of Berger's workload. These included media duties at the Nurburgring on Sunday.
Frederic Elsner, previously in charge of series management, will focus on developing the fan experience.
Speaking to Autosport's German-language sister title Motorsport-Total, Biermaier expressed confidence in Tomczyk - who drove for Abt between 2001 and 2010 - and said he had full trust in his abilities.
"Apparently Martin has learned relatively much at Abt that he can now take over the task!" he said.
"No, joking aside. I think Martin is absolutely the right one because he has a lot of experience, because he knows the DTM inside out - and now he has seen the whole thing from a different perspective in the first few months.
"I can only congratulate him. He is absolutely the right man and I am looking forward to working with him."
Asked if Tomczyk could follow in Berger's footsteps at some point, Biermaier added: "I think so. Martin has good contacts, a good name, a clean appearance.
"He has the historical knowledge and feeling. And he can also negotiate well. I definitely trust him to do that. That's very positive!"
Speaking to Autosport on Sunday at the Nurburgring, Tomczyk said he wasn't thinking about his future too much and stressed that he and Berger are "in one line together" with respect to developing the DTM "in a very healthy and good way".
"I like in the here and now," he said.
"I want to fulfil the job as good as I can, and that's I think the main part why I'm in the present now and don't look too much in the future."
On Saturday during the lengthy fog delay, Tomczyk went on track with Berger and race director Scot Elkins to determine whether conditions were suitable for racing.
He cited Elsner's call to issue free tickets for Sunday's Nurburgring race for Saturday attendees as "exactly what we wanted to achieve with that sort of restructure, so we can react now quicker, more precise and faster".
"Luckily, it's an increasing volume of workload that we are facing, and to make that happen in a very precise and direct way we restructure internally," Tomczyk said.
