Stewart Cink opened up a five-shot lead at the halfway stage of the RBC Heritage after firing back-to-back rounds of 63. Cink followed an early eagle at the second with six birdies as he raced to 16 under par, dropping only one shot over the first 36 holes to become the oldest player to hold the halfway lead in the history of the tournament in South Carolina. Overnight leader Cameron Smith slipped seven shots off the pace, while Dustin Johnson safely made it