The fun didnt last long, giving way to 1.8 inches of rain on the already-saturated Glen Abbey course. Soon after Dufner finished the second round in light showers, the heavy rain forced tour officials to postpone the third round until Sunday morning.
Four inches of rain have fallen since the event began Thursday.
In an attempt to get 36 holes in on Sunday, the tour cut to the low 60 and ties instead of the usual low 70 and ties, leaving 64 players in the tournament. The players will go off in threesomes and wont be regrouped for the fourth round.
Dufner eagled the par-5 13th to reach 9 under for the round, but played the final five holes in even par ' birdieing the par-5 16th, dropping a stroke on the par-4 17th and saving par on the par-5 18th after hitting into the water.
I played very well, hit a lot of fairways, a lot of greens. Made a couple more putts, Dufner said. It started raining at the end, conditions got a little tougher, but 63 is a pretty good score, and leading after two rounds is always great.
At 13 under, Dufner had a one-stroke advantage over Jerry Kelly (67) and 2001 winner Scott Verplank (67). Nathan Green (65), Peter Tomasulo (68), Martin Laird (69), Pat Perez (67), Bob Estes (67), Retief Goosen (69) and first-round co-leaders Camilo Villegas (71) and Kevin Na (71) were 10 under.
If youve been out here long enough, youre used to this, Verplank said. Theres no reason to get all worked up about it because theres nothing you can do about it. I think everybody wants to play 72 holes and get a good tournament in. This is a big tournament for me, so wed just like to do it the right way and, if we have to stay here a little longer to get it done the right way, then so be it.
Calcavecchia opened the delayed second round with two pars, then reeled off nine straight birdies. His nine birdie putts were from 15 feet or closer. With 15-year-old son Eric working as his caddie, Calcavecchia shot a 65 to reach 8 under.
Its just fly it right to the stick, Calcavecchia said. You give the guys out here no wind and greens that are plugging, youre going to see a lot of low scores.
Calcavecchia broke the record set by Bob Goalby in his 1961 St. Petersburg Open victory and matched by Fuzzy Zoeller (1976 Quad Cities Open), Dewey Arnette (1987 Buick Open), Edward Fryatt (2000 Doral-Ryder Open), J.P. Hayes (2002 Bob Hope Classic) and Kelly (2003 Las Vegas Invitational).
The streak ended on the par-4 third when the 49-year-old players chip from over the green went 5 feet past. He saved par to remain 10 under, but dropped a stroke on the par-3 fourth after hitting into a greenside bunker, and bogeyed No. 8.
I think adrenaline kicked in a little bit, even more than it already was, said Calcavecchia, the 2005 winner at Shaughnessey in Vancouver, British Columbia.
Leif Olson and Casey Wittenberg had holes-in-one on the par-3 15th, the fourth aces of the round on the 132-yard hole ' and the only ones on the hole in 25 Canadian Opens at the course. Olsons ball caromed off playing partner Kris Blanks ball. All four players won 2009 BMW Z4 Roadsters.
There have been six aces overall, the most since the Tour began keeping extensive records in 1971. There were five in the 2004 John Deere Classic.
Canadians Mike Weir (66) and Stephen Ames (69) were 7 under. Pat Fletcher was the last Canadian winner, taking the 1954 event at Point Grey in Vancouver.
Weir was back on the course for the first time since opening with a 71 on Thursday in a round delayed 7 1/2 hours because of rain.
This has been such a crazy week, Weir said. At least today, I was able to play 18 holes and actually get in some kind of a rhythm.
Former Southern California player Jamie Lovemark, making his pro debut, followed an opening 74 with a 66 to finish at 4 under.