The Paris - Madrid race, which generated considerable interest and was eagerly awaited by the general public, was organised in three stages over a total of 1307 km, but was unable to meet these high expectations and ended in nothing short of disaster. Out of 315 registered vehicles, a total of 224 appeared at the start in Versailles, including 88 cars in the heavy class from 650 to 1000 kg and 54 motorbikes. The first participants were set on their way on 24 May at 3:45 a.m.; the last one finally started three hours later at 6:45 a.m., by when the first had already covered a good 200 km. Tens of thousands of spectators lined the streets. Visibility was extremely poor due to the dust stirred up by the numerous vehicles, and spectators kept crowding onto the track. This resulted in numerous accidents in which seven people - the drivers Marcel Renault and Claude Loraine-Barrow, three mechanics and two spectators - were killed and many others were injured, some of them seriously.
As a result, the race was stopped by the French authorities in Bordeaux, at the end of the 552 km-long first stage. This went so far as to ban the drivers from moving their vehicles even one metre further. The journey back to Paris had to be made by train, and cars were not even allowed to make the journey to the station under their own power. For DMG, the race was deemed to have been a failure. In addition to six brand-new 90 hp racing cars, five 60 hp and one 40 hp car were also on the grid. The best-placed Mercedes in the end was a 60 hp car, in which John B. Warden achieved fourth place in the heavy car class. The fastest 90 hp, driven by Camille Jenatzy, finished in 11th place. The other four cars that crossed the finish line were all behind the 60 hp and even behind the 40 hp, which finished in 12th place with Max at the wheel. The disastrous outcome of the event made the mediocre performance of the Mercedes-Simplex 90 hp fade into the background a little, but nevertheless showed that there was a need for action.
This was also stated in the report in the "Allgemeine Automobil-Zeitung" of 31 May 1903: "The Mercedes were disappointing. It seems to be the brand's fate to lose out in the main event of the year after triumphing in the spring. Until now, this has been understandable, as the Mercedes cars launched early in the year provided the French manufacturers with a welcome guideline as to how powerful they needed to make their racing cars for the forthcoming season. That was not the case this time, because the 60 hp Mercedes were there for the first races of the season, and the 90 hp Special cars for the big events. The former had delivered what was expected of them, but not the latter. A 60 hp Mercedes belonging to Mr. Warden has beaten all 90 hp Mercedes, and even the 40 hp Mercedes driven by Max was faster than the 90 hp of de Caters, Hieronimus and Werner. The performance of the 40 hp car should actually be the pride of the Daimler factories. But where were their 90 hp cars? They failed. It is said that the cooling-water tanks were too small to cool the machine sufficiently. This is quite possible, because the beehive of the 90 hp is smaller than that of the 60 hp. Why? The weight had to be less than 1000 kg, and since there was not a single gram to be saved anywhere, the radiator was reduced - as experience has taught us, this was an ill-advised economy. Nor was it particularly helpful that the cars went into the race almost directly from the factory."