Constant heavy rain led to a second 30-minute postponement of Saturday's qualifying session for Sunday's potentially title-deciding United States Grand Prix.

The session was due to start at 1300 local time (1800GMT) following heavy storms that also led to delays and cancellations on Friday as the Circuit of the Americas was buffeted by heavy rain, the collateral damage of Hurricane Patricia battering Mexico.

Opening free practice took place in damp conditions, but second practice on Friday afternoon was called off.

The third and final free practice session took place in very wet conditions and was curtailed by heavy rain on Saturday morning when the track was closed to fans until after noon.

Defending two-time world champion Lewis Hamilton of Mercedes, who is hoping to win Sunday's race to clinch his third world title, was fastest in that session ahead of nearest title rival four-time champion Sebastian Vettel of Ferrari.

Many fans, who were allowed into the circuit after the morning lockout, complained at their treatment and at being prevented from seeing any cars in action on the track.
 Source: AFP