Who has the edge in Sepang after a too-close-to-call Friday?

Formula 1's return to Sepang for the Bahrain Grand Prix in Malaysia got off to a competitive start, with the top four teams within four tenths of a second of each other in second practice. But who is showing signs of emerging as the one to beat as degradation dominated the radio and post-session chatter?

Let's cut to the chase. Who are the favourites?

I'm not trying to dodge the question, honest – but it's really too close to call according to our data.