Russell Henley followed his opening 62 with a 64 to take a four stroke lead into the weekend at the Wyndham Championship in North Carolina but there were mixed fortunes for the Irish duo of Padraig Harrington and Seamus Power.
Harrington missed the cut on two over after a difficult second day which saw the three-time major winner card a six-over-par 76.
The Dubliner managed five birdies but his round was punctuated by three double bogeys as well as four further dropped shots.
Power, meanwhile, just made the cut by one stroke on three under after a level-par 70 which also featured five birdies.
But the Co Waterford native carded three bogeys as well as a double bogey on the Par-3 12th.
But it's Henley who leads the way. The American dropped a shot on the 12th, his third hole of the day, but was otherwise in fine form and picked up seven birdies to double his overnight lead.
Olympic silver medallist Rory Sabbatini also carded a 64 to jump 18 places up the leaderboard for a share of second on 10 under, alongside Webb Simpson and Scott Piercy.
Justin Rose is tied for third on nine under and going birdie-bogey-eagle between the 13th and 15th, while American Tyler Duncan is also third after shooting a 62 on Friday.
Among those to miss the cut alongside Harrington were Martin Laird and Hideki Matsuyama.