FORT WORTH, Texas, May 25, 2013 (AFP) - Kuchar was among 54 players who had to return in the morning to complete the second round after weather delays on Friday.
The American finished 36 holes with a one-stroke lead over Canada's Graham DeLaet, then fired a one-under par 69 in the third round, for an 11-under total of 199.
He had a one-stroke lead over DeLaet, Boo Weekley, Matt Every and Chris Stroud.
"This morning feels like a day ago," Kuchar said. "It would've been nice to extend my lead. Tomorrow will be an exciting day."
Kuchar, who won the WGC-Accenture Match Play in Arizona in February for his fifth US tour title, will be trying Sunday to join world number one Tiger Woods as the US circuit's only multiple winners this season.
Four more players were two strokes off the lead: South African Tim Clark, John Rollins, Steve Flesch and Martin Flores.
Another 10 players were within four strokes of the lead that included defending champion Zach Johnson, who headed a group of four players on 202, and 19-year-old local favorite Jordan Spieth, who was among six players on 203.
"It's going to be a shootout," Weekley predicted of Sunday's final round.
DeLaet led by two midway through the third round, after Kuchar took back-to-back bogeys at the seventh and eighth.
But DeLaet couldn't bring it home, bogeying three of his last six holes as Kuchar birdied the 11th and the 16th to climb back into the lead.
DeLaet birdied the last to complete a 69 and seize his share of second.
Every and Weekley both climbed the leaderboard with third-round 66s, while Stroud posted a 67.
Spieth had a share of the lead when he birdied the par-four fifth -- his third birdie of a round that he launched with back-to-back birdies.
However, he bogeyed the sixth, one of four bogeys on a card that also included a double-bogey five at the par-three 13th.
"I just made some mental errors -- just rookie mistakes that cost me about four shots," said Spieth, who shot a one-over 71.
Leading third-round scores on Saturday in the $6.4 million US PGA Crowne Plaza Invitational (USA unless noted, par 70):
199 - Matt Kuchar 65-65-69
200 - Matt Every 65-69-66, Chris Stroud 67-66-67, Boo Weekley 67-67-66, Graham DeLaet (CAN) 64-67-69
201 - Martin Flores 66-70-65, Tim Clark (RSA) 67-69-65, John Rollins 63-71-67, Steve Flesch 68-64-69
202 - Bud Cauley 67-69-66, Jonas Blixt (SWE) 67-68-67, Zach Johnson 69-65-68, Freddie Jacobson (SWE) 66-67-69
203 - Charley Hoffman 66-70-67, J.J. Henry 68-68-67, Scott Stallings 69-65-69, Chris Kirk 67-66-70, Jordan Spieth 65-67-71, Josh Teater 65-67-71
204 - Ted Potter 70-66-68, Brendon de Jonge (ZIM) 66-70-68, Tommy Gainey 65-72-67, Chez Reavie 70-64-70
205 - Hunter Mahan 69-68-68, Jason Kokrak 66-71-68, Jim Furyk 69-66-70, Bo Van Pelt 70-68-67, Ben Kohles 67-67-71, Brian Davis (ENG) 67-68-70, Daniel Summerhays 65-73-67, Ryan Palmer 62-72-71