Ferrari blame wheel nut for Vettel's missed podium

By Alan Baldwin SPIELBERG, Austria (Reuters) - Ferrari blamed a wheelnut for robbing Sebastian Vettel of a podium appearance at the Austrian Grand Prix on Sunday and said it must not happen again. With Ferrari chairman Sergio Marchionne watching, Vettel pitted in the lead -- after the dominant Mercedes drivers had already stopped -- and lost an agonizing amount of time as mechanics wrestled to remove the right rear wheel. Vettel rejoined in fourth place and was unable to get back in front of Felipe Massa's Williams for what would have been the German's sixth podium finish in eight races for the Italian team. "We got the problem with the wheelnut and it's not the first time so we have to make sure that it does not happen again," Ferrari principal Maurizio Arrivabene told reporters. "It was not a problem of the mechanics, it was our problem and we have to make sure we fix it. "Sebastian made a very good race but we threw away the podium one more time for a stupid piece that needs to be fixed as soon as possible. For me it is not acceptable," he emphasized. Vettel, the four-times Formula One champion who joined from Red Bull at the end of last season, remained third overall in the championship with his team mate Kimi Raikkonen the big loser after crashing out on the opening lap. "The issue during the pit-stop is something that can happen: I had a problem, but generally the guys are the quickest on the pit lane so there’s nobody to blame," Vettel said. "We are a team and when you push to the limit these things can occur. "Today was a bit disappointing because we’ve lost the podium, but I’m sure tomorrow it will be better and we’ll focus on the next race." (Editing by Ed Osmond)