Jhonattan Vegas was in front for first time in a major and didn’t back down Friday in a PGA Championship filled with drama everywhere but the top of the leaderboard.

Looming large amid an eclectic mix of contenders was Scottie Scheffler, still not in full control of his game but only three shots back going into the weekend.

Vegas cruised through the back nine at muggy Quail Hollow and was 10-under par until he missed a 3-foot putt on 18 and ended an otherwise splendid day with a double bogey for an even-par 70, giving him a two-shot lead.

“Every chance you get to lead a major and play with the lead is never easy,” Vegas said. “So I feel proud of a solid round today.”

He was at 8-under 134, two ahead of Matthieu Pavon of France (65), former U.S. Open champion Matt Fitzpatrick (68) and Si Woo Kim, the engaging South Korean who made an ace on the longest par 3 at Quail Hollow on his way to a 64. Kim hit 5-wood on the 252-yard sixth hole, making it the longest hole-in-one in major championship history

Defending champion Xander Schauffele had a stressful afternoon just to make the cut and extend his streak to 64, the longest on the PGA Tour since Tiger Woods set the record at 142 tournaments 20 years ago.

Rory McIlroy had another tough day off the tee, and perhaps one reason for hitting only 10 out of 28 fairways over two rounds came from news that developed late in the afternoon. Sirius XM PGA Tour Radio was first to report his driver was tested and deemed not fit to play under USGA regulations.

The test was Tuesday and McIlroy had to find a new driver to put in play. For the second straight day, the Masters champion and latest member of the career Grand Slam club declined to speak to the media.

McIlroy missed a 3-foot par putt on the 17th and then hooked his tee shot left of the creek near the hospitality tents, lucky it caromed back into thick grass right of the creek. He needed to two-putt for bogey from 35 feet for a 69 to make the cut on the number.

The Grand Slam club most likely stays at six members the rest of the year — Jordan Spieth rallied with a 68 but missed the cut by one shot, leaving him a PGA Championship short of getting all the majors.

Phil Mickelson could still win the U.S. Open for the Grand Slam at age 54. He certainly didn’t look the part when he took four swipes at the ball to get out of a bunker on No. 12 and wound up with a quadruple-bogey eight. He made seven birdies in a round of 72.

Now it’s about 36 holes to chase after the 27-pound Wanamaker Trophy, which might feel even heavier to so many players in the mix who are newcomers to major pressure.