The 21-year-old trailed West Australian Daniel Fox by two shots with four holes left, but produced an eagle on 15 to grab a share of the lead.

Armstrong easily reached the 484m par-five, while Fox missed the green long and left.

Fox left his approach short and knocked his next to within three foot for par, leaving the rookie with a tricky 3m putt, which he nailed.

"I didn't hit too many fairways early on that back nine, so it was good to get that one, it's a pretty tight tee shot and I finally got one down the middle," Armstrong explained.

"I had a comfy yardage for my second and hit a really nice shot to about 10 feet right under the hole and was fortunate enough to roll it in."

On the 207m par-three 16^th, Armstrong retained the momentum by hitting a long iron to around 4m.

Fox's tee shot clipped a tree around 75m from the green and while he produced a strong approach, it rolled 2m off the back of the green and he was unable to make the par putt.

Armstrong's attempt just missed, but the par was enough to steal a one-shot lead.

Fox had a left to right breaking putt on the 18^th to force a playoff, but it shaved the cup on the low side and didn't fall.

Armstrong had backed up his equal course record (with playing partner Charlie Dann) 63 on day one with a four-under 69 for a total of 132, a shot ahead of Fox (64, 69), who was one in front of Dann (63, 71).

The Concord member pocketed just under $9000 in the inaugural $50,000 event, which is part of the NSW Regional Series.

"I had got a bit 'steery' is probably the right word off the tee early on the back nine, I was trying to get it on the fairway," he offered.

"We had a wait on the 15^th tee and it just allowed me to get back on track.

"It's my first win as a pro, so it's nice to get that early."

Armstrong only turned pro in December.

Meanwhile, Corowa Golf Club professional James Gordon played superbly to finish tied for fifth on eight-under, including the equal best score of the second round with 66.

And Wodonga's Daniel Gill was the leading amateur on three-under after rounds of 71, 72.

PGA Australia and Golf NSW officials were delighted with the event.

ALSO IN SPORT:

Many of the players will now contest the next event in the State regional series in Dubbo, starting Saturday.

The $50,000 events continue at Queanbeyan (February 24-25) and the South Coast Open at Moruya on February 28-March 1.