The Italian driver had been running sixth when he and Audi stablemate Nico Muller were both penalised for allegedly speeding during a Virtual Safety Car period, Mortara dropping to 17th as a result.

While he recovered to finish third in Sunday's second race, it means Mortara now trails championship leader Marco Wittmann by 17 points.

Governing body DMSB later admitted that there were "probably deviations" between the stewards' GPS data that they use to administer speeding penalties and that of the Audi cars themselves.

"This is really bitter because, as a result, Edo lost at least eight points which might decide the championship at the end of the season," said Gass.

"In addition, Audi Sport Team Abt Sportsline has lost the lead of the teams' standings and we've lost points in the manufacturers' classification because Edo finished in position 17 instead of six.

"The mistake that happened there is hard to accept."

Mortara added: "I did nothing wrong. That's also obvious based on the on-board footage from my car and our data log.

"We didn't score the points at Zandvoort we would have deserved. Due to the penalty on Saturday, we lost eight to 10 points that we would have urgently needed in the championship race.

"Although the podium on Sunday feels good it doesn't erase what happened in the first race."

DTM championship standings:

Pos. Driver Car/Team Points 1 Marco Wittmann BMW/Team RMG 105 2 Jamie Green Audi/Team Rosberg 98 3 Edoardo Mortara Audi/Team Abt 88 4 Robert Wickens Mercedes/HWA 83 5 Paul di Resta Mercedes/HWA 74 6 Maxime Martin BMW/Team RBM 63 7 Nico Muller Audi/Team Abt 62 8 Mattias Ekstrom Audi/Team Abt 58

The DMSB statement added that future penalties for speeding will only be awarded after the race following the Zandvoort episode.

"During the race, we have to be able to rely on the technical systems made available to us," said race control spokesperson Michael Kramp.

"When the system is reporting that somebody is speeding, an immediate penalty is inevitable.

"Therefore, race control will refrain from using the GPS data to control the slow zones until the situation has been fully clarified.

"When a slow zone would be necessary during the race, any speeding infringements will only be analysed and penalised after the race."