Mercedes had a big advantage on the timesheets after the first day of free practice for the Abu Dhabi Grand Prix, but an edge of just under four tenths might prove to be an illusion.
While Valtteri Bottas set the pace, he is using a brand new power unit after suffering a failure at the Brazilian Grand Prix. This means two things: first that the quicker Mercedes driver on Friday will start at the back, whatever happens. But there's a second and more significant factor.
Much of the rest of the field is using tired engine packages, or running conservatively with aged ones they need to get one more race out of, so we perhaps shouldn't get too excited about the performance difference.