Mercedes driver Lewis Hamilton celebrates after finishing third in the Bahrain Formula One Grand Prix on April 4. Photo: IC

Lewis Hamilton has been hit with a five-place grid penalty for Sunday's Chinese Grand Prix because of a gearbox change, Mercedes said Thursday.

Already trailing teammate Nico Rosberg by 17 points after the German won the season's first two races in Australia and Bahrain, Hamilton will now face a battle to prevent that gap from widening in China.

"This weekend is going to be tough," Hamilton posted on his Instagram site alongside a photograph of fans in Shanghai welcoming him at the airport.

"I will start with a five-place grid penalty due to a gearbox change but because of you guys I feel energised, motivated, and confident that we can regain ground lost."

Mercedes determined that China was the best place to change the gearbox, which was damaged in Bahrain and needed replacing.

"Not the ideal start to the weekend, admittedly, but of all the places to take a grid hit, this is one of the better ones," Mercedes tweeted.

Under Formula Ones rules, drivers have to use a single gearbox for six successive races, meaning the highest grid position Hamilton can now hope for on Sunday is sixth.

Hamilton has had more success in Shanghai than any other Formula One driver. The Briton has won four times in Shanghai and is on for three in a row after last season becoming the only driver to win the race in successive years.

Hamilton has not won since he took his third world championship in Austin, Texas, in October but the 31-year-old has started both races this season on pole position.

First win

Rosberg has reasons of his own to be confident in Shanghai.

His first Formula One victory came in Shanghai in 2012 and he stands on the cusp of history with only three other drivers ever putting together a run of six or more wins in a row - two of them also Germans.

Sebastian Vettel managed nine with Red Bull in 2013 and Michael Schumacher seven with Ferrari in 2004. The other was Italian Alberto Ascari in the 1950s.

Mercedes have won the last eight races but Hamilton, 17 points behind Rosberg, is not the only threat to the championship leader.

Rivals Ferrari have yet to show their true pace, and might have won earlier without mishap, but Vettel and Kimi Raikkonen can count on plenty of local support in a country where red is a lucky color.

In Bahrain Vettel did not even start, his Ferrari engine coughing out plumes of smoke on the formation lap, but there will have been plenty of work back at the factory since then.

"We are pushing very hard and we know that we can still improve," Vettel said after Bahrain.

Ferrari's most recent winner was Fernando Alonso, in 2013.

The Spaniard,  now at McLaren, who fractured ribs in the season's first race, has been given provisional clearance to race on Sunday, the governing International Automobile Federation said Thursday. Alonso was forced to sit out the last race in Bahrain on doctors' orders after he failed a medical following an horrific accident in the Australian Grand Prix that left him with fractured ribs.