American golfer Ben Martin stretched his lead to three strokes by firing a five-under-par 67 on Friday in the second round of the PGA Tour's Zurich Classic.
Martin, who has made just two cuts in his past 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 on 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-4 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.
