One of our mowers had a hydraulic leak on Saturday at the start of 11 fairway, making a line of burnt grass in it's wake. The grass that was covered with hot oil will not recover, but with most of the damage in the rough it won't take long for the surrounding turf to fill in the void as soon as the oil in the soil dissipates.
Damage in the fairway, operator turned the machine around not knowing there was a leak.
Unfortunately it is one of the downfalls of heavy machinery, inevitably things fail despite proper upkeep.