Rain had fallen throughout the night on the Lancashire coast and was still sheeting down as the 137th Open got underway at 6.30am with Australian Craig Parry striking the first tee shot into the gloom.
Added to the rain was a strong wind that reached 30mph in some places, making accuracy an even more vital commodity on an unforgiving Royal Birkdale course.
It soon became apparant that level par or just over would be a good score in these treacherous conditions as every player struggled to contain the elements.
Reigning champion Padraig Harrington only confirmed he would defend his title after testing his injured wrist on the practise range an hour before he was due to tee off.
Harrington, who beat Open favourite Sergio Garcia in a play-off last year to lift the Claret Jug, had picked up the injury defending his Irish PGA title and abandoned his practise round on Wednesday after just nine holes to have treatment.
His defence did not get off to the best of starts as he bogeyed the first hole.