Rory McIlroy in Irish Open contention after third-round surge
Northern Ireland's McIlroy was eight shots behind the lead at the halfway stage of the tournament.
But he made the most of a faltering display from the overnight leaders to move to 11 under par, two shots behind Hurly Long.
The German, ranked 252nd in the world and without a top-25 finish this season, posted a 70 at the K Club to end Saturday on 13 under, a shot ahead of England's Jordan Smith.
The final group of Smith, India's Shubhankar Sharma and England's Ross Fisher were a combined nine over par for the front nine and six over par at the finish.
McIlroy's fine round was almost derailed at the 16th hole when the four-time major winner found the water with his second shot.
His fourth from the drop zone hit a rock on the edge of the hazard only for a lucky bounce to propel the ball onto the green.
McIlroy was just off target with a long putt for par but recovered to finish his round with birdies at the 17th and 18th holes, the latter following a 346-yard drive and nine-iron approach to the 548-yard par-five.
"To bounce back with the two birdies on 17 and 18 after putting the ball in the water on 16 was huge, so overall a great day's play," said McIlroy.
The 2016 Irish Open champion added: "I didn't feel like I did anything very special, but it added up to a great score and I've gotten myself a lot closer to the lead when last night (Friday) I thought I was maybe a little bit too far behind and out of it.
"It's hard to try to win your national Open and try to get over the line. I'm excited to have another opportunity."
There were problems for McIlroy earlier in his round when he broke his three-wood following a poor tee shot on the sixth hole.
"I went to hit the top of that tee-marker and I caught the corner with the bottom of the shaft," explained the 34-year-old.
"It was just a flick. I've done it a couple of times before this week and everything went okay, but that one didn't."
