Chinese Grand Prix 2016: Ferrari show pace to challenge Mercedes as Kimi Raikkonen tops practice in Shanghai

Raikkonen was a quarter fo a second faster than Nico Rosberg with Lewis Hamilton nearly half-a-second shy of the Ferrari

(Getty)

Sebastian Vettel has warned Mercedes that there is more to come from Ferrari after the Italian team beat their rivals to a practice one-two ahead of the Chinese Grand Prix.

Kimi Raikkonen posted the fastest time of the day at the Shanghai International Circuit with Vettel a tenth of a second shy of his team-mate.

Nico Rosberg, winner of both races this season and fastest in the opening session, was a quarter of a second slower than Raikkonen, while Lewis Hamilton, who will be demoted five places on the grid following a gearbox change, was 0.433 seconds adrift of the Finn.

"Overall, I think we can still improve," said Vettel, who failed to score any points last time out in Bahrain following an engine problem. "The balance is not yet where I want it to be, so let's see what we can do.

"I think we had a decent day, the car feels okay for one lap. The feel was okay, but okay is not good, so I think we can still improve - especially the balance of the car - so, there is a lot of work to do tonight trying to get on top of everything."

Despite Vettel's reserved comments, Ferrari will be pleased with a display which has been their most promising of the season so far. But for Formula One's all-conquering Mercedes team, who have won 34 of the last 40 grands prix, their day was far from smooth-sailing.

Hamilton, who can start only from sixth even if he qualifies fastest on Saturday following his penalty, spun twice in the opening session and also ran off the road at turn one later in the day. And while Rosberg may have topped the timesheets on Friday morning, the conclusion of that session was blighted by an ignition problem.

"The Ferraris are particularly strong so it looks like we're going to have a real fight this weekend," said Hamilton, who is yet to win a race since he clinched his third championship at October's United States Grand Prix.

"I'm behind them which means it is going to be harder to overtake them so getting into the top three is going to be hard on Sunday for sure.

"It seems that we're going to have a bigger fight than we ever have, so it should be good for the fans."

Sebastian Vettel followed his Ferrari team-mate in second (Getty)

The opening practice session had been overshadowed by three tyre blow-outs. Felipe Massa encountered two issues with the left-rear wheel of his Williams, while Renault's Kevin Magnussen also suffered a similar problem.

Massa re-emerged for the day's second session, with a set-up change to their car, and they suffered no further issues with Valtteri Bottas 10th and Massa 14th in the timings. The cause for Magnussen's blow-out was blamed on a suspension problem with Pirelli, the sport's sole tyre supplier, not at fault for either of the three incidents.

Lewis Hamilton struggled throughout both sessions (Getty)

Meanwhile, Fernando Alonso, who missed the last race in Bahrain following a rib injury sustained after a horror crash at the season-opening Australian Grand Prix, has also been allowed to race here this weekend.

The Spaniard was required to undergo a medical examination after opening practice, but was given the all-clear by the FIA. He finished the session in 11th, one place ahead of his McLaren team-mate Jenson Button.

"There was a little bit of pain, which is no surprise as the rib still has a little bit of a fracture," said Alonso. "But the pain is manageable and there is no other risk with being in the car, so that positive thing."

PA