The DTM sporting regulations have been constantly changing over the last few seasons, recent major alterations including a second race per weekend, a shift in the way the success ballast is apportioned, and a move back to a single tyre compound.

Pitstops currently aren’t used for the short race on Saturday, while the Sunday race has a single compulsory stop that must be made during the middle third of the race, and during which all four tyres must be changed.

According to 2012 series champion Spengler, the regulations are getting closer to being right for the category. However, he says Saturday’s race should be longer, and that the pitstop window should be abolished, giving teams the opportunity to pit as often or as little as they like.

He says that, coupled with a softer tyre compound, would create the best racing.

“I think the race format is almost right,” he told Motorsport.com. “What I would do, maybe, is do a longer race on Saturday with pitstops.

"I would also leave the pitstops open, how many, when, all of that. Whatever you want to do.

“We need a softer compound tyre, too. It should just be one compound, like we have now, just something that degrades more. After five or 10 laps, there should be a big tyre degradation.

“That would force the teams and the drivers to do a strategy, a real strategy. Some can maybe try and run through the race, the whole race, and others go more aggressive and have to do two stops.

“It would just open everything up.

“I think we’re not far away from something really good right now. If we did these adjustments, it would be very interesting.”