Fox, playing for a maiden European victory and a place in the Open in two weeks’ time, says he has had an attacking mindset all week and won’t be changing ahead of the final round.
South Africa’s Erik van Rooyen leads at 14-under after a brilliant 66 around the Ballyliffin GC with Fox and Sweden’s Joakim Lagergren sharing second at 10-under.
“It's going it take birdies to win it,” Fox said bluntly after a Saturday 70.
“I don't think Erik is going to come back too much. It's going to require a decent round of golf, and 5, 6-under has been a tough score to get this week.
“So I'll be trying. We'll see what happens. I'm not going to change the mind-set.”
Fox began the third round sharing the lead with van Rooyen and France’s Matthieu Pavon but battled to an outward nine of 1-over with one birdie and two dropped shots.
As he did Friday, however, he finished strong with three birdies and no blemishes on the inward half to stay in touch with the South African who looked to be running away with the tournament after going out in a stunning 6-under 29.
But a run of nine straight pars kept the field in touch and gave Fox some hope for Sunday’s final round.
“I guess thankfully for the rest of the field, he cooled off a little bit on the back nine but it's going to take something seriously special to catch him tomorrow,” Fox said of the South African.
“I've taken the golf course on the last three days and it seemed to work. It's going to be very condition-dependent again but if we get a day like this, I'll be doing what I did: Hit driver everywhere and try to hit wedges in and see if I can hole some putts.
“I've been lucky, I guess we've taken the theory that bogeys aren't a bad score. I've been driving the ball really well and made a couple bogeys from bad tee shots but given myself a lot of chances from good tee shots.
“As I said the last couple days, it does depend on conditions a little bit and if we get a day like today, it's worth taking the golf course on.”
Fox will play alongside former Masters champion Danny Willett Sunday in the second to last group, the Englishman alone in fourth at 9-under.
Tournament host Rory McIlroy endured another disappointing day to sign for an even par 72 and remain 1-under and T33.
The four time major winner has a chequered history at his national championship with five missed cuts and a win in the past six years.
His ball striking has been excellent all week but he has struggled with the putter and continued the trend on day three.
“Just sort of struck in neutral this week and hopefully finish off with a good one tomorrow,” he said.
“Pretty similar to the last couple of days. Hit the ball pretty well. A couple of loose shots here and there, and holed a couple of putts out there I guess.
“Greens with that little bit of rain coming in in the middle of the round, I felt like the greens must have slowed up a little bit. I struggled to get the ball to the hole the last few holes.”
Adam Bland is the best of the Australians at even par and T41 after a 1-under 71 while Wade Ormsby dropped 33 places on the leaderboard to T63 with a 4-over 76.
DUSTIN JOHNSON'S UNIQUE ACTION:
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