The Webex Players Series Sydney champion is co-leader with Will Florimo after opening with a 6-under-par 66 on the St John Course at Heritage Golf and Country Club.

They lead six players – Order of Merit No.2 Cameron John, Lachlan Barker, Josh Armstrong, John Lyras, Louis Dobbelaar and American Chris Malec – by a shot.

In great form since the Christmas-New Year break, O’Donovan was in a great position to challenge for the inaugural ISPS HANDA Japan-Australasia Championship and move into the No.1 spot in the Order of Merit race in his rookie season as a professional, until he was brought undone by a final round of 5-over-par 77.

From a tie for fourth at the start of the day, he ended up tied 35th with his chance at winning the OOM gone – for this season at least.

“I probably just wanted it a little bit too much, to be honest,” O’Donovan said after his morning round in the Yarra Valley.

“I play my best golf when I’m not looking at the leaderboard, and I’m just focusing on the shot in front of me.

“I knew I needed to play well on Sunday and didn’t really start how I wanted, and then I was kind of just forcing good shots and not giving myself any room for error.”

In the best of the morning scoring conditions, O’Donovan played his opening nine holes, the back nine at Heritage, in 6-under-par 30 before settling for nine straight pars on his second nine.

“I played great on my front nine and then actually I still played great on my back nine, the actual front nine,” he said.

“I hit a ton of good shots, ton of good putts, and honestly just nothing happened. I wouldn’t really change any of the shots I hit or any of the lines I picked.”

Being at the top of the leaderboard at Heritage is not unusual for Will Florimo, who led at the halfway point in this tournament 12 months ago before finishing in a tie for 12th, six shots behind the winner, James Conran.

After starting with rounds of 68-65, the lefthander closed with 70-69 over the weekend.

“I seem to like the place. I seem to make a lot of birdies out here, and I think that’s what you’ve got to do,” Florimo said.

“If I learned one thing last year – I took the lead into the weekend – I think I had one bogey for the weekend and got lapped. You’ve just got to keep the pedal down out here.”

Florimo was part of the hottest group on course on day one, playing alongside John Lyras, who had the lead at 7-under-par before two late bogeys saw him card a 67, while Nathan Barbieri signed for a 68.

“Johnny got off to a great start, and I actually horseshoed the first two holes, which was not that kind,” Florimo said.

“Between the three of us, we made a bunch early, and it’s always a good visual to see some going in and hitting them close.”

Off the back of his win in Auckland on Sunday, Order of Merit No.1 Travis Smyth started with a 3-under-par 69, two shots behind No.2 Cam John, whose 67 matched the best round in the afternoon groups.

OOM No.3 James Marchesani has some ground to make up after a 3-over 75.