World Champion Jenson Button and his team mate Lewis Hamilton made it two out of two for McLaren as they topped a Friday practice session each of this racing weekend at Shanghai. Button was quickest in the morning (full times) while Hamilton bettered that time mark in the afternoon (full times).

Nico Rosberg had a good day out in his Mercedes GP car finishing second in both the sessions and again, ahead of his team mate, the more illustrious Michael Schumacher. Schumacher was a full eight-tenths slower in the first session but reduced that to just twenty-five hundredths in the second session, in what was the closest margin yet to his younger mate this season. Hamilton was third in the morning while Button took that place in the afternoon. Both clocked 312 km/h at the speed trap down the back-straight and were the fastest speeds in both sessions.

McLaren are expected to do well this weekend, barring of course any stupid decisions they make like staying in the pits early during Q1 at Sepang. The reason is the F-duct which will come in great use while driving down the two fast straights of the Shanghai circuit. They are also bringing aerodynamic updates to the race – though nothing to do with suspensions – and will be eager to lock horns with Red Bulls in qualifying.

Other teams have started testing their own versions of the F-duct. Sauber already employed it in the Malaysian GP and here Ferrari and Williams are testing their own interpretations, though won’t be racing them just yet. Even Sebastien Vettel has said that Red Bull need their own system in place as well for it accounts for nearly five-tenths down the straights. None of the new systems when in place will be as refined as the McLaren one for the cars have been homologated and only the Woking team will be affecting the vent on its nose. In that sense, it is really important for them to make best use of their system here, for possibly in Barcelona, Ferrari will be racing theirs and Red Bull testing one – both teams deciding to test race pace on Friday and hold their qualifying cards close to the chest.

Ferrari though have added problems here. Fernando Alonso blew his engine in the first practice session and didn’t set a time. Leave aside the track time lost, it might escalate into an engine reliability problem for the Scuderia. They also provide units to Toro Rosso and even they have suffered a loss in the first three races. Talking of Toro Rossos, Sebastien Buemi had a massive shunt down the back straight in the morning session (see video). One wonders what he must have felt losing his tyres just like that and it is indeed the safety wonders of modern day Formula One that he was able to walk away from this incident.

Talking Indian interests, Karun Chandhok was quickest amongst the new teams for a short while in second practice before settling for 21st, still ahead of Lucas di Grassi’s Virgin and Hispania team-mate Bruno Senna. Force India had Adrian Sutil running in the top ten in both sessions but if they really need to get a heads up on Renault and Williams, and make work their talk of hauling in Mercedes, they need both cars there.