Cameron Tringale and Andrew Landry share the lead heading into the final round of the John Deere Classic, while Ireland's Seamus Power endured a disappointing third round.
Power, who played himself into contention with a 65 in the second round, hit a four-over 75 to leave him way off the pace on Saturday.
The Waterford man hit three birdies throughout the front and back nine, but his progress was hindered by two double bogeys and three bogeys.
Sitting on four-under overall, he now 12 shots off the American pair heading into the final round.
Tringale and Landry hold a one-shot lead over the chasing pack, with Tringale carding a 65 and Landry a 67 to leave the duo on 16-under.
Their compatriots Bill Haas and Adam Schenk were the closest challengers, sitting just a shot further back.
Colombia's Jhonattan Vegas had held the lead at the midway stage but a poor round saw him drop out of contention as he slipped to eight shots behind Tringale after a round of 76 as good as ended his hopes of victory.
Nick Watney, Sepp Straka and Sebastian Munoz moved into contention after matching Haas for the best third-round score, each carding 64.
England's Luke Donald was left with little chance of success, sitting on seven under par ahead of the final round, while Scotland's Martin Laird was just two shots better off.
