SEVEN-TIME champion Michael Schumacher has admitted a lingering neck injury is hampering his sensational return to racing.<br /><br />The German, 40, has been coaxed out of retirement by former team Ferrari while Felipe Massa recovers from a fractured skull suffered at last month’s Hungarian Grand Prix.<br /><br />But Schumacher says his training for the European Grand Prix later this month has aggravated a neck problem he sustained in a motorbike accident in February. “I’m currently in the midst of my preparations for the upcoming race. I have already lost three kilograms, even if it is also important for me to build up muscles,” said Schumacher.<br /><br />“All in all, the training is going pretty well, although I have to admit my neck pinches a bit. We have to get a grip on that as health has priority. That’s the clear arrangement made with Ferrari and, by the way, with my wife too.”<br /><br />Ferrari, meanwhile, have hit back at Williams for denying Schumacher a test session in their F60 car. The Italians wrote to all of their rival teams asking them to make an exception to the rule that forbids testing in between races, but Williams led the objections.<br /><br />“Guess who opposed the test with the F60?” said Ferrari on its website. “A team that hasn’t won anything for years and yet didn’t pass over the opportunity to demonstrate once more a lack of spirit of fair play.”<br /><br />Red Bull and Toro Rosso also opposed the move, arguing that newcomer Jaime Alguersuari was not granted similar dispensation before his first race last month.