Contradictory day for pace-setting Lewis Hamilton on and off the track in China

On a day of apparent contradiction at Mercedes, Hamilton was overheard telling his pitwall "something is still not right with the car" even after setting the quickest time of the day.

If that wasn't sufficiently curious, Hamilton then denied holding clear-the-air talks with Nico Rosberg that his team-mate was adamant had taken place on Thursday night.

With the two Mercedes drivers the championship favourites, any hint of discord between Hamilton and Rosberg will be seized upon by both the media and their flagging rivals.

Indeed, while Mercedes remain the overwhelming favourites heading into the weekend, on the evidence of Friday's practice sessions both Ferrari, for whom Fernando Alonso was quickest of all in Practice One and second fastest in the the afternoon session, and World Champions Red Bull may have closed the yawning gap in the wake of the Silver Arrows' relentless domination two weeks ago in Bahrain.

"Ferrari seem to be close so we need to keep pushing," conceded Rosberg.

Despite taking top spot in the timesheets, Hamilton endured a particularly troubled day, missing almost an hour of track time after a suspension problem was detected on his W05 car.

"[I've not learnt] much. It's not been the easiest of days," Hamilton told Sky Sports afterwards. "This evening we have got to do some work to figure out where we are. Obviously we are not that bad, but you always want to be better and we will work hard tonight to find some improvements on set-up.

"The [suspension] problem put us on the backfoot because you don't have many laps as it is and so every lap counts. But we will fix whatever problem we had and be quick tomorrow."

Even more curious was the mixed messages from the Mercedes camp on the purported post-Bahrain debrief between Hamilton and Rosberg.

"Yes we sat down and went through everything, it's all behind us and flat-out ahead," said the German after Friday practice.

But when asked about the cited debrief, a bemused-looking Hamilton shook his head and flatly denied any meeting had taken place. Asked if his relationship with Rosberg was still 'cool', Hamilton replied: "As far as I'm aware, yeah."

Speaking to reporters on Thursday night, Rosberg sought to diffuse any suggestion of a rift between himself and Hamilton, but did admit that he was unhappy with one of the Englishman's moves as he defended his lead in Bahrain.

"The majority was tough but respectable, so let's go with that, rather than pick out one small example," said the German when questioned about his radioed complaint to the Mercedes pitwall.

"It is completely normal for teams after races where a lot has happened that you sit down and discuss what has happened and we will do that - we are going to do that today."

Saturday's qualifying session, exclusively live on Sky Sports F1, takes place at 7am.