HOCKENHEIM Germany - Red Bull and Ferrari considered filing a protest after dominant Formula 1 team Mercedes switched its brand of brake discs without penalty before the start of Sunday's 2014 German GP.Ferrari team principal Marco Mattiacci told reporters after championship leader Nico Rosberg won the race for Mercedes with team mate Lewis Hamilton third: "We discussed it internally... we decided not to move forward with it."CLARIFICATION NEEDEDHamilton crashed during qualifying on Saturday (July 19) after a front brake disc failed. He raced with a different brand while Rosberg changed the rear discs on his car.Although the governing International Automobile Federation said the change was within the regulations, Red Bull principal Christian Horner suggested the decision had set a precedent.Horner told reporters: "It is a change of car specification. If you change it like for 'like' that is one thing, but if you change it for something that is made by a different manufacturer that has a different characteristic, as described by the driver himself as something different, then it is an interesting precedent."Horner, who said both his drivers had raced with Brembo brake discs similar to those used by Hamilton in qualifying, felt there was a need for further clarification from the federation."Obviously if you can do that (change discs), then what else can you change? It will be interesting to see what the justification of that allowance was."Mercedes has won nine of the 10 races so far in 2014; Red Bull won the other.Stay with Wheels24 for the 2014 F1 season – fresh reports every day.