Jones is two shots behind the joint leaders, Jordan Spieth and Zach Johnson who in turn are one shot ahead of Rory McIlroy, Peter Malnati and Brian Harman.
Jones is playing his 11th event on the PGA Tour this season and has yet to record a top 10 finish, his best coming when 13th at the AT&T Byron Nelson event in Dallas a month or so ago.
His record in this event hardly gave rise for confidence given he had missed three of his last five cuts at the TPC River Highlands so this is an encouraging start for the former Australian Open champion.
Jones was quickly out of the blocks today when 4 under par through just five holes of his round and although the momentum slowed thereafter he did add another birdie at his 16th hole to get to 5 under.
The highlight of Jones’ round came at the par 5 3th (his 4th hole) where his second from 240 yards finished just ten feet from the hole and he converted for eagle.
Day played his final nine holes well after roller coaster opening nine holes and although he has played this event sparingly over the years and not well when he has done his start was a good tonic after the disappointment of last week's US Open.
Geoff Ogilvy recorded a round of 68 before heading for a stint in the commentary box where host Mike Tirico was heard to say that if he had 68 on the golf course he had produced a 63 in the the booth.
Marc Leishman was perhaps the surprise of the rest of the Australians given his very good previous record in the event. Leishman was round in 4 over par 74 today to be in 138th place and will need a round of 4 or 5 under tomorrow just to make the cut.
Of the leaders Jordan Spieth is the defending champion having defeated Daniel Berger in a playoff last year in what was his only start in the event to date. Spieth was delighted to have finally made a good start but is keeping things in perspective.
"I've been very positive about making progress from how I got pretty off earlier this year," he said after his round. "So it's good to see a good score. Those are obviously nice to see, but still a long way to go. It's round one. Just glad. The first rounds have been kind of detrimental to me, so it's nice to be in the thick of things.
"I would probably call it third best of the year, behind the first and last round at Augusta. I had a good one at Houston I remember. But, yeah, this golf course I played it really smart today. It was probably the smartest round I've played this year, really the last couple years."
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