NEW ORLEANS, April 26, 2014 (AFP) - Martin, who has made just two cuts in his last nine tournaments but finished third in both, completed 36 holes at 15-under 129.
"It was nice to kind of validate what I did yesterday getting off to a hot start," said Martin. "I wasn't worried about what had happened previously or what was coming up. I wanted to just try to do that again on the second nine."
Martin is seeking his first career win on the North American tour.
"Overall, I don't think it could have gone much better," Martin said.
Andrew Svoboda carded a four-under 68 to remain in second place at 12-under 132, while Robert Streb (66) and South Korea's Noh Seung-Yul (68) shared third at minus-11 at the TPC Louisiana.
Erik Compton (68) and Peter Hanson (69) are tied for fifth at 10-under 134.
Martin began his round Friday on the 10th tee with a two shot lead on the field.
He added to his advantage by landing his second shot at the par-four 10th to within a foot and rolling that in for a birdie.
He pulled further ahead by chipping for an eagle at the 11th, and reached 14-under with a seven-foot birdie putt at the 13th.
He added a short birdie putt on his final hole, the ninth, to finish at 15-under.
No one was able to threaten Martin's lead until Svoboda took the course in one of the final groups of the day.
Svoboda is seeking his first top-10 finish in his 33rd career USPGA Tour start.
Scores after Friday's second round of the $6.8 million PGA Tour's Zurich Classic (par 72, USA unless noted):
129 - Ben Martin 62-67
132 - Andrew Svoboda 64-68
133 - Seung-Yul Noh (KOR) 65-68, Robert Streb 67-66
134 - Peter Hanson (SWE) 65-69, Erik Compton 66-68
135 - Charley Hoffman 68-67, Jeff Overton 67-68, Keegan Bradley 69-66
136 - J.B. Holmes 71-65, Will Wilcox 68-68
137 - David Duval 68-69, Retief Goosen (RSA) 72-65, J.J. Henry 68-69, Bo Van Pelt 74-63, Graham DeLaet (CAN) 69-68, Chad Collins 66-71, Kevin Kisner 69-68, Mark D. Anderson 72-65, Tommy Gainey 71-66, Michael Thompson 66-71