MANCHESTER —With 156 players and no available open date on the other side, Augusta Country Club and the Maine State Golf Association had a tight window to squeeze the Charlie’s Maine Open through in its entirety.

Thunder, lightning, heavy rain and ultimately standing water slammed that window shut Monday afternoon.

After a two-hour delay and no abatement in the weather made it unlikely that some golfers even would get to start their round before nightfall, officials canceled the first day of the event.

Eighteen players completed their round and dozens more were on the course when the sirens sounded to stop play shortly after the noon hour.

None of their scores will count. The Maine Open now becomes a one-day, 18-hole Tuesday event. Monday’s tee times will apply.

“We can’t go into Wednesday, because there is a schedule conflict with both the New Hampshire Open and the Pro Senior Championship,” MSGA executive director Nancy Storey said.

Players and officials waited in the clubhouse and cafeteria for two hours while rain, ranging from moderate to heavy, descended upon a course that already was wet from Sunday’s storms.

Significant puddles formed on the 11th and 18th greens and in the fairways, visible from Route 202 on the Manchester-Winthrop line. Even if the rain stopped by mid-afternoon, it would have taken an additional hour or more to prepare the course for play.

“Every 10 minutes of this just saturates the course more and more,” said Mike Doran, the MSGA’s director of player development.

The cancellation was bad news for many players who went out early and shot a red number. Those now become practice rounds.

For the second time in three years, Jesse Larson of Mendon, Vt., was the early clubhouse leader. He shot 66.

Past champions John Hickson of Topsham and Jerry DiPhilippo of Gorham and Eric Egloff of Sandy Spring, Md., each carded 67.

“My hip and lower back were so bad, I thought it was going to be a long day,” Hickson said. “I didn’t hit it that good. I shanked it around, but I made a few putts.”

Defending champion Evan Harmeling shot 68.

Local amateurs Andrew Slattery of Minot and Brian Bilodeau of Auburn each broke par with 69. Slattery won the Maine Amateur at Woodlands Club in Falmouth earlier this month.

“We only got soaked on 18. We got the best of it, I think,” Slattery said. “We heard a rumble of thunder on the 18th tee and it was like, ‘Oh no, don’t stop us now.’ This is a fun one. It’s not as stressful as the amateur. It’s more relaxing. Just go out and try to put up a really good number.”

Slattery was the second-low amateur in the 2013 Open.

J.J. Harris of Bath and another previous winner, Michael Carbone, were 4-under after the front nine. Harris was playing the 18th when the horn sounded.

Larson carded birdies on holes 6, 7, 10, 12 and 16 before bogeying 17.

Egloff played a bogey-free round, beginning with nine consecutive pars and capped with a birdie.

The tournament is scheduled for 36 holes and must conclude Tuesday, with many of the same players set to tee off Wednesday in the New Hampshire Open.

NOTES: Rain also plagued Sunday’s Pro-Am, which is the lone annual fundraiser for the MSGA scholarship fund. Despite a brief lightning delay, that event was completed in five hours. Bangor native Jesse Speirs was low pro with a 67. Joe Alvarez shot the low amateur round of 69, leading his team of Staci and Karlton Creech and Harris to victory. Karlton Creech is athletic director at the University of Maine … Two-time WMSGA amateur champion Alexa Rancourt is the lone woman in the field. She will tee off with Nathan Fairfield and Ron Bibeau at 1:10 p.m. Tuesday … David Chung, who won the Greater Bangor Open in a fourh-hole playoff Saturday, never had the opportunity to start his round. He is scheduled for a 12:30 p.m. start … Harmeling, Hickson and Geoffrey Sisk, who finished at 71 before the rain Monday, are among the 10 past winners in the field.