SAN DIEGO, Calif., June 19 (Reuters) - Russell Henley held his nerve and a two shot lead midway through the third round of the U.S. Open on Saturday with a pack of major winners breathing down his neck at Torrey Pines. Henley, who shared an overnight one shot lead with Englishman Richard Bland, doubled that advantage when he rolled in a 12-foot birdie putt at the ninth to get to one-under on the day and six-under for the tournament. Bland"s front nine included a single bogey but the 48-year-old journeyman was also holding steady two back of the front-running American. Henley might want to avoid the temptation to glance up at the leaderboard because if he does he will see some of golf"s biggest names and major winners in hot pursuit. Defending champion Bryson DeChambeau and four-time major winner Rory Mcllroy are lurking just three back with world number three Jon Rahm and South African Louis Oosthuizen one further adrift. World number one Dustin Johnson closed with two birdies for three-under 68 to jump up the leaderboard sitting five back. McIlroy staged a back nine charge to card a four-under 67 and move into contention for a fifth major title. The Northern Irishman started the day six off the pace and could not get much going on his outward nine that featured a single birdie. But he was dialed in after the turn mixing a bogey with four birdies, including a chip in from 95-feet at the 12th and another at the 18th, to take the clubhouse lead at three-under. Phil Mickelson, a record six-times U.S. Open runner-up, saw his bid to complete the career grand slam disappear for another year after a sloppy five-over 76 left him at seven-over and 13 back of the leading Henley. Playing a month after becoming golf"s oldest major winner at 50 by claiming the PGA Championship, Mickelson could not produce the same magic in his home town turning in an ugly scorecard his two birdies offset by five bogeys and double bogey at 17.