Victorian Luke Bleumink carded a 6-under-par, 64, for a one-stroke lead over Russell Henley of the University of Georgia and David Chung of Stanford University.
Bleumink shot 32-32 on the 6,871-yard course, holing out from 61 yards for eagle on the par-5, 3rd hole only to finish in style with a 60-foot putt for birdie on the par-4 17th.
"I was happy with my game and just played solid," said the 25-year-old Bleumink, who was co-runner-up along with Jin Jeong to Matt Jager at this year's Australian Amateur Stroke Championship in Perth.
"It was pretty hard out there on the course with the gusty winds, but I putted well so that kept me in it. It's pleasing to be where I am and to in with a good showing."
First round play was suspended due to unfavourable weather conditions on a day where only twelve players that completed their rounds broke par.
"It was tough and you had to hang in there and not think about what number you were scoring because of the conditions," said Bleumink, who's playing in his third Porter Cup.
"I've been here before and know a little how the ball rolls on the greens. That certainly helped me today. Tomorrow, I'll try and go out there and do it again, that's the plan."
British Amateur Champion, Jin Jeong, is the next best placed Aussie opening with a 1-under-par 69 to be in a share of 8th place.
A stroke behind Jeong is Matt Jager, Jason Scrivener and Jordan Sherratt with the Australian trio opening with an even par, 70, to be in a tie for 16th.
The Porter Cup is Jager's season debut here in the US after a recent stint in the United Kingdom and the world number 13 will be looking to go one better than his runner-up finish to Mark Anderson at the 2008 Players Amateur, his best result so far in the US.
Jeong has rightfully claimed the world number 1 position and enters this week at Niagara Falls as the tournament favourite in a field that's littered with US and international talent. His opening even par round has done his chances no damage as he's only five behind Bleumink.
Daniel Beckmann is currently at 2-over-par and in a tie for 40th position, along with Bryden Macpherson. Kieran Pratt opened with a 3-over-par, 73, with Ryan McCarthy and Tarquin MacManus at 4-over-par after opening with a 74.
Brendan Smith, who lead the opening round of the Porter Cup last year, rounds out the Australian contingent with a 6-over-par, 76.
Last year in a rain effect tournament that was reduced to three rounds, Brendan Gielow won the Porter Cup after going in to a three-way playoff with Andrew Yun and Cody Gribble, when the three finished at 6-under-par.
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