Darren Clarke took the outright lead in the British Open early into Saturday\'s third round using his expertise in wet-weather play to cope with the dreadful playing conditions. The popular 42-year-old Ulsterman started the day tied for the lead at four under with American Lucas Glover and he struck immediately with a birdie at the first. Glover bogeyed, allowing Thomas Bjorn of Denmark to move into second at four under with a birdie at the first but he then bogeyed the fourth to hand Clarke a two-stroke lead. Miguel Angel Jimenez of Spain parred the first three holes to stay at three under, but PGA Champion Martin Kaymer of Germany and American Chad Campbell both dropped back to two under alongside Dustin Johnson. Up ahead, Rory McIlroy was battling hard to keep his hopes alive of winning back-to-back Majors as the stormy weather lashed the 71 Open survivors. Last month\'s US Open champion started the day on level par, handily-placed four shots off joint leaders Clarke and Glover. With the rain increasing in intensity and the gusting wind turning shot selection into a lottery, the 22-year-old Ulsterman, playing for the third straight day with young American Rickie Fowler, pulled off a thick pair of gloves and promptly clattered his opening drive into heavy rough left of the fairway. He slashed his second into a bunker and failed to get up and down from there as he slipped back to over par territory. Another bogey followed at the par-three third, but he also had birdie opportunities at two, four and five as he grafted away to stay in contention. He then bagged his first birdie of the day at the par-five seventh, while Fowler fell back to one over with a bogey at the 11th. Tied for 19th at the halfway stage it was a different prospect for McIlroy on Saturday as he had led after the first two rounds of the year\'s first two Majors, The Masters and the US Open. The early scores in the clubhouse reflected the conditions with 1999 Open winner Paul Lawrie taking an 81, and with 78s going to England\'s Paul Casey and Frenchman Gregory Havret, who had a 10 at the par-five 14th. Related article: Open heartbreak for Westwood and McDowell But it was US veteran Tom Watson, who had a hole-in-one at the sixth on Friday, who once again was a standout as he parred the first six holes and then grabbed a birdie at the par-five seventh. Another long putt to save par at the eighth left him as the only player at that stage under par for the day and at one over for the tournament, still in contention for a record-equalling sixth Open win. He finally succumbed to the weather, coming down the back nine with four bogeys, but at four over he was able to sit back and see how the leaders coped with the conditions. With the worst of the storm expected to have moved through the area by 4:00 pm, the leaders looked set to enjoy a huge slice of luck.