Troy Matteson had a pair of bogeys on the back nine Saturday, but still carded a 5-under 66 to keep his lead at the John Deere Classic.
Matteson finished 54 holes at 18-under-par 195 and is three clear of the man who has owned this event recently.
Three-time defending champion Steve Stricker also shot 66 to move into second place at minus-15. He is looking to become the fifth player to win the same tournament four straight years.
"I have a good time here. Obviously, a lot of good vibes going around here having won the last three years," Stricker said in a televised interview. "You know things start to happen for me here. I made some putts."
Zach Johnson, the 2009 runner-up, shot 66 to finish three rounds at 14-under- par 199. He was joined in third place by Brian Harman (69).
Billy Hurley III fired a 7-under 64 at TPC Deere Run to jump into a share of fifth at minus-13. He stands alongside J.J. Henry (69) and John Senden (67).
Matteson 2-putted for birdie on the second and made it two in a row with a 9- foot birdie effort at the third. He moved to 16-under with an 11-foot birdie putt at No. 6.
The two-time PGA Tour winner ran home a 27-footer for birdie at the 10th, but gave that shot right back at the 11th. He drove into the trees and had to chip out.
Matteson's third stopped 41 feet from the hole and he 2-putted for bogey. He atoned for that mistake with a birdie from off the green at the 13th.
After a pair of pars, Matteson kicked in a 3-footer for birdie on the 16th. He followed with a 2-putt birdie from 35 feet out at 17. At the last, Matteson 3- putted for a closing bogey to cut his lead to three.
"It was interesting. I hit a few bad ones and few good ones and made a couple of long putts," Matteson said. "It was an interesting way to play the back. I've played really well and have gotten away with a few things and that's what you need to do to stay near the top."
Stricker was even-par through seven holes. He started to make his move with a 4-foot birdie putt at the eighth. Stricker sank an 8-footer for birdie at 10 to move to 12-under.
The three-time defending champion briefly got within one thanks to a hot stretch late on his back nine.
Stricker tapped in a short birdie try on the 14th and came right back with a 4-foot birdie effort at 15. He converted a 6-foot chance for birdie at 16 and made it four in a row with an 11-footer for birdie at 17.
That run got him within one of Matteson's lead. However, Stricker scrambled to a bogey at the last to slip to 15-under.
"A lot of holes fit my eye and there are a lot of short iron shots," Stricker said on TV. "If you drive the ball in the fairway, you have a lot of short iron shots and that's my strength. And my putter is starting to warm up a little bit. I've just got to keep plugging along."
NOTES: Matteson will look to become the third wire-to-wire winner in event history on Sunday...This is the first time he has had three straight sub-par rounds since the 2011 Transitions Championship...Matteson has a piece of the 54-hole lead for the sixth time in his career and he has won two of the previous five.