Walker clings to lead halfway through final round

By Larry Fine SPRINGFIELD, New Jersey (Reuters) - Jimmy Walker was one stroke ahead at the PGA Championship heading to the final nine holes with defending champion Jason Day and British Open winner Henrik Stenson chasing him. Walker parred his way through the front nine to remain on 11 under par, while Day and Stenson stood at 10-under, one better than clubhouse leader Branden Grace of South Africa, who shot a three-under 67 for a nine-under total of 271. Australia's world number one Day followe