The U.S. Open got behind schedule Thursday because of heavy rain, and no one is sure when it will end.

Water covered the greens and created tiny streams in some fairways, forcing the first round to be suspended after 3 hours, 15 minutes of play. No one played more than 11 holes.

The 78 players who started will resume play at 6:30 a.m. Central time this morning. If weather allows the first round to be completed, the second round will begin later today and continue until it is dark.

Tiger Woods was 1 over par, 2 strokes behind, and faced a 10-foot putt for par on No. 7 when play was stopped.

Real trouble could come later if the weather improves and mud sticks to golf balls. The USGA is adamant that players not be allowed to lift, clean and place golf balls — a standard practice on the PGA Tour.

And make no mistake — this championship will be played over 72 holes.

“I guarantee you, they will have a U.S. Open champion at the end of this week,” said Padraig Harrington, who won last year’s British Open and PGA Championship but was 4 over when play was stopped.

Then he paused and corrected himself.

“Well, at some stage in the next week.”