NICHOLASVILLE, Ky. — A thunderstorm suspended the fourth round of the PGA Tour's Barbasol Championship until Monday morning.

Sunday's third stoppage of play at Champions Trace at Keene Trace Golf Club came with the four leaders — Hunter Mahan, Robert Streb, Tom Lovelady and Troy Merritt at 18-under par — and four other contenders waiting to begin the round.

The tournament will resume at 7:30 a.m. on Monday. Lightning caused one delay, and play was stopped earlier in the afternoon to clear water that accumulated on the course following a morning of steady and sometimes-heavy rain.

Inclement weather has plagued the tournament throughout the weekend. The second round was completed Saturday morning after being suspended by thunderstorms late Friday afternoon.

Tournament director Steve Carman said the goal was to complete play Sunday but that "Mother Nature didn't give us a very good shake."

"Our goal is to finish 72 holes, and that includes on Monday," he added. "We've got about four hours and 30 minutes of golf left to play. If we get suspended, we've got until dark to get it in because the goal is 72 holes.

"If the forecast was such that it was completely unreasonable for us to expect to be able to play, then the scenario would be that we wouldn't play on Monday and we would consider going back to 54 holes. But that's not in the cards right now."

The resumption will mark the PGA Tour's second Monday finish this season. Jason Day won the Farmers Insurance Open in January after darkness delayed the sixth playoff hole, and he needed just 13 minutes to claim the victory.

Monday morning's forecast is a more promising with partly sunny skies, a high temperature of 72 degrees and a 20 per cent chance of rain.

The tournament will pick up with the contenders finally starting play while others aim to finish a weekend of fits and starts of play. Just 21 golfers finished before play was suspended.