Matteson shot a 10-under 61 at the TPC-Deere Run course to take a three-shot advantage.
He came to the par-4 ninth, his last hole, needing to hole his second shot from the fairway to shoot a 59. He missed the green, but salvaged par for his low round of the season.
Matteson has won twice on the tour, but has missed the cut in half his tournaments in 2012.
Stricker is trying to become the fifth player in golf history to win the same event four consecutive times. The most recent to do so was Tiger Woods, who captured the Bay Hill Invitational four times in a row beginning in 2000.
Stricker's round was highlighted by an eagle at the par-4 14th, where he holed his second shot from 79 yards out.
Scott Piercy, K.J. Choi, Brian Harman, Luke Guthrie and Gary Christian joined Stricker at 65.
Ted Potter, who won his first tour event last week at the Greenbrier Classic, shot a 67. John Daly reached 3-under for his round, but suffered a late bogey and double bogey to finish at even-par 71.