The 27 year old US born but Mexican citizen leads Australian golf's flagship event by five shots and the manner in which he handled the windswept Lakes Golf Club layout in Sydney today suggests he will be a hard man to get past tomorrow.
Twelve months ago Ancer was 261st in the world but in the period since he has moved inside the top 100 and a win here will obviously advance his cause even further, likely inside the top 60.
Ancer has won only one event on a recognised professional tour in his career to date but he has created a great opportunity to add to that by taking a five shot lead into the final round at the Lakes Golf Club.
Ancer began the day two shots behind the 36 pace set by Ben An and Max McCardle but it was a run of five consecutive birdies from the 6th hole that swept him into the lead.
A bogey at the 11th was the result of a pulled tee shot and a poor lay up at the par 5 but his gamble with a driver at the short par 4 13th paid off with his 7th birdie of the day before adding further birdies at the 16th and 17th for a round of 65 the equal best of the week and at 13 under he leads by five.
Ancer was asked as to this was one of his best rounds. "I think so I mean there are a couple of rounds maybe last year I think I shot 8 under in the Quickens Loans event that was a course record on a tough golf course but conditions wise I think this is up there for sure.
"It was a tough round I knew I just had to stay patient and keep the ball in play I was able to do just that. Whenever something did not go my way I was able to make, at most, a bogey which out here is pretty good."
So what would a win tomorrow mean to him? "It would be awesome. I have never been to Australia and I have seen the names on the trophy - very inspiring some of who who I know and have played on the PGA Tour and it will mean the world to me."
The second placed Keita Nakajima continues a great run by amateur golfers this week, the Japanese player who won the Australian Amateur Championship earlier this year, moving past the man he beat in the final of that event David Micheluzzi to claim the lead in the race for the leading amateur.
Keita Nakajima hits his approach to the 11th.
Nakajima, who despite winning the Australian Amateur Championship and finishing runner-up to his fellow countryman Takumi Kanaya at the Asia Pacific Amateur, is currently ranked 92nd in the World Amateur rankings but he is likely to receive a significant boost in his standing in the game as a result of his efforts this week.
It is not beyond the realms of possibility that Nakajima could become the first amateur to win this event since Aaron Baddeley's win 19 years ago.
Keegan Bradley in action today and still a chance despite being six behind.
Keegan Bradley, and Marcus Fraser are tied for 3rd at 7 under and although six shots from the lead, today showed that massive swings are still possible on this course.
Australians Dimi Papadatos, Matt Kuchar, Aaron Pike and Cameron Percy are another shot back in a share of 5th and perhaps the only remaining players with a realistic chance of winning although they will need something very special and a little help from those ahead.
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