UPDATE 1-Golf-Calcavecchia birdie record brightens gloomy Open

* Calcavecchia reels off birdie record

* Stormy weather ends play

(Adds suspension of play and cut)

By Steve Keating

OAKVILLE, Ontario, July 25 (Reuters) - Mark Calcavecchia reeled off a PGA Tour record nine straight birdies on a wild day at the weather-hit Canadian Open but it was Jason Dufner who took the midway lead on Saturday with the round of the day.

After two days of almost steady rain softened up the Glen Abbey course, golfers went on the attack and Dufner stormed to the top of the leaderboard with a nine-under 63 in the second round, one stroke off the course record set by Greg Norman in 1986.

Chasing his first PGA Tour win, the unheralded Dufner hit a birdie at the 16th to get to 10 under but he gave it back on the next hole, carding his only bogey of the day to leave him with a total of 13-under 131 and a one-shot lead over fellow Americans Jerry Kelly (67) and Scott Verplank (67).

Lurking one stroke further back on 11 under were Australia's Nathan Green (65) and American Peter Tomasulo (68) with Colombian Camilo Villegas (71), South African Retief Goosen (69), Briton Martin Laird (69) and Americans Pat Perez (67), Bob Estes (67) and Kevin Na (71) sitting three off the pace.

"It started raining at the end making conditions tougher but 63 is a pretty good score," Dufner, 32, told reporters. "I saw this morning on the board walking from the car that the course record was 62.

"But you just try to shoot the best score that you can and the records just kind of come."

Calcavecchia, the 2005 champion, played the back nine first and started his day with pars at 10 and 11 then fired nine consecutive birdies on his way to a seven-under 65 to sit five strokes behind the leader.

GOOD SHOTS

Calcavecchia's string of nine birdies was one better than the previous record of eight shared by six golfers.

The 49-year-old American's sizzling run stalled with a par at the third then came to a screeching halt with a bogey at the par-three fourth.

"It was exciting, it's just fun to hit good shots every hole," said Calcavecchia, who had his wife on his bag at the British Open but switched caddies this week in favour of 15-year-old son Eric.

"Am I disappointed in a 65? Yeah, a little bit. I played the last seven holes two over but if you told me I was going to make nine birdies and shoot seven under I would have taken it."

The third round had been scheduled to get underway later on Saturday but torrential rains swept across the already water-logged layout, forcing a premature end of play for the second straight day.

Officials said they would attempt to pack in 36 holes on Sunday but with more stormy weather forecast the 100th edition of the Canadian Open appeared to be heading towards a Monday finish.

Chez Reavie will not be among those getting an early wake-up call on Sunday as the defending champion failed to make the three-under cut.

Also getting the rest of the weekend off were fan favourite John Daly and 2008 U.S. Masters champion Trevor Immelman.

Casey Wittenberg also missed the cut but will drive away in a new sportscar after his hole-in-one on the par-three 15th.

Leif Olson also aced the 132-yard hole, bringing the total number of aces in two rounds to six, the most in any tournament since the 2004 John Deere Classic.

(Editing by Clare Fallon; To query or comment on this story email sportsfeedback@thomsonreuters.com)