American Billy Horschel produced a masterful round in atrocious conditions on Saturday to lead the British Open as the field bunched up for what promises to be a thrilling conclusion to the battle for the Claret Jug at Royal Troon.

While the Ayrshire links released its grip earlier in the day to allow several players to zoom into contention with sizzling third rounds, the leaders faced heavy rain and a chill wind in what became a battle for survival.

Florida native Horschel, playing in shirt sleeves when everyone else was decked out in waterproofs, carded a 2-under 69 to head into Sunday's climax at 4 under.