Unheralded Englishman Daniel Brown shot into a shock lead of the British Open at six under par as Rory McIlroy was among the big names to struggle on day one of the 152nd British Open at Royal Troon.World number four Ludvig Aberg was another of the big names to falter in his first ever round at a British Open with a four-over round of 75. kca/pi/ea/pb