Toto Wolff has revealed that he is carrying a 'lucky injury' into the 2017 season.

The Mercedes chief revealed to the Stuttgarter Zeitung newspaper that he recently damaged a disc in his back during a tennis coaching session with his 12-year-old daughter.

"The coach put tennis balls on the court for a sprint exercise. When the coach said a good time was 22 seconds, I thought 'Great, it's about the stopwatch'," he explained.

"I started out and thought 'I'm faster'. By the fifth ball I turned around and felt fire. It was a disc."

However, there is a silver lining. In 2014, Wolff broke several bones in a cycling crash. In 2015, the 45-year-old damaged his knee at the gym. Both times, Lewis Hamilton went on to win the world championship.

"It's a good sign for Lewis, because every time I hurt myself, it works out for him," Wolff said.

However, in winter testing it was clear that Ferrari has taken a big step forward for 2017, while Wolff is also refusing to rule out Red Bull as a challenger.

"The tests showed that it is tighter between Red Bull, Ferrari and us," he said. "Then there is a gap.

"Our car did not behave as we expected, especially in the second week, but we will only know what is actually going on after qualifying on Saturday."

The new seasons begins this weekend with the Australian Grand Prix.