Wolff fears freak injury for Hamilton

With Lewis Hamilton on the verge of capturing a fifth Formula One world title, Mercedes team boss Toto Wolff revealed he's living in dread of the Briton suffering a "freak" injury -- especially to one of his fingers.

Hamilton opened a 67-point lead over Ferrari's Sebastian Vettel with four races left after storming to victory in Japan at the weekend, but Wolff clearly wants to wrap his star driver in cotton wool for the remainder of the season.

"Absolutely freak incidents happen everywhere," said the Austrian. "I don't want to even think about him breaking a finger!"

Hamilton could put Vettel out of his misery if he wins the next race at Austin in two weeks and Vettel finishes lower than second -- or if he outscores the German by eight points.

But Wolff has warned against complacency after Vettel could only finish sixth following an early collision with Red Bull's Max Verstappen.

"It's important to stay concentrated," insisted Wolff. "You either have the trophy in your hands or you don't -- and we haven't got it in our hands."

"A bad result suddenly wipes off a large chunk of your points," he added.

"It doesn't look likely, but this is motor racing. It's a sport, anything could happen. I don't want to dwell too much about it because it's bad karma too, so let's just go to Austin and get it done."

Hamilton was cock-a-hoop after leading a Mercedes one-two for his sixth win in seven races and fourth in a row.

It was also his 71st Formula One victory and 50th for the Silver Arrows.

Standing over his car, the Briton said: "Austin is usually a good track for us, so I can't wait to unleash this beast there."