Shawn Stefani managed a 1-under 70 on Friday to keep his lead after two rounds of the Tampa Bay Championship.
Stefani, whose best tour finish was a share of 36th last year at the Houston Open, finished 36 holes at 7-under-par 135.
K.J. Choi briefly joined Stefani in the lead, but bogeyed the 16th to fall one back. Choi parred the final two holes for a 4-under 67. He shares second place with Adam Scott (66) at minus-6.
Jason Dufner also fired a 66 to move into a share of fourth place at 5-under- par 137. He was joined there by Peter Tomasulo (68) and a pair of former Georgia Bulldogs -- Harris English (69) and Brian Harman (70).
Stefani ran off five straight pars to start his round. His second shot from the rough at the sixth stopped nine feet from the hole and he converted that birdie effort.
The 31-year-old gave that stroke right back as he stumbled to a bogey at the seventh. Stefani erased that mistake with another 9-foot birdie putt at the eighth on the Copperhead Course at Innisbrook Resort and Golf Club.
Stefani failed to keep his momentum though. He drove well left off the 10th tee and had to pitch back to the fairway. His third stopped 21 feet from the hole and he 2-putted for bogey.
After four pars in a row, Stefani drained a 14-footer for birdie to get back to minus-7. He finished there as he parred the final three holes.
"Today was a little bit more of a struggle ball-striking. I didn't really drive it super great. Didn't hit some of the best iron shots, but scrambled well and I putted really great," Stefani stated. "When you putt good, that usually keeps rounds going, and that was pretty much what happened today with the result of my 1-under par."
Scott started on the back nine and chipped his third to three feet at the 11th and rolled that in for birdie. At the next par-5, the 14th, he converted a 15- foot birdie try to move to minus-3.
The Australian parred his next four before 2-putting for birdie from 13 feet out at the first. He poured in a 28-foot birdie effort at the par-3 fourth.
Scott made it two in a row with a 7-foot birdie putt at the fifth. He parred the final four holes to wrap up a bogey-free round.
"I played the (par-5s good). I don't know, the score might have dominated them," Scott said of the four par-5s. "I got up and down from a couple good spots. That's kind of my game plan around here is to play fairly conservative. The course can come up and bite you. My game is to take advantage of the par-5s when I can. All went to plan today."
Choi eagled the first from 16 feet out. He birdied the sixth, but stumbled to a bogey on No. 8 to dip back to the minus-4.
The 2002 and 2006 champion got up and down for birdie on the par-5 11th before converting a 9-foot birdie chance at the 13th.
Choi rolled in a 15-foot birdie putt at the par-3 15th to join Stefani in the lead. However, he dumped his second shot into a bunker at the 16th and that led to a bogey, which dropped him one back. Choi parred the final two holes to end in a share of second.
NOTES: Defending champion Luke Donald stumbled to a bogey at the 18th to slip to even-par 142 after a second-round 72, which left him tied for 31st ... The cut line fell at 2-over-par 144 with 77 players advancing to the weekend ... Among those missing the cut were Louis Oosthuizen, 2011 winner Gary Woodland, two-time winner Retief Goosen, 2005 champ Carl Pettersson and David Toms.