The Northern Irishman revealed he had some work to do on the range following an opening 72 and it looked to have paid off as he produced five birdies in a bogey free effort to get to five under.
He made a birdie on the tenth despite finding sand off the tee at the par five and then made birdies from 17 and seven feet at the 12th and 15th.
A two putt birdie on the 17th was followed by an approach to 15 feet at the first and while McIlroy was frustrated not to pick up any further shots, the four time Major winner was happy with his day's work at Mount Juliet Estate.
"There's a lot of people between me and the lead so I need to go out there tomorrow and shoot something probably a little better than I did today to give myself a real chance on Sunday," he said.
"I need to at least get into double digits under par by the end of tomorrow to give myself a chance and there's a bit of weather coming in as well and we'll see how that goes. I don't think I'm right back in contention but I'm pretty close.
"I did some practice last night and figured a couple of things out and to play the first nine holes in four under was nice and being five under through ten, I thought I was on course for something a bit lower than five under in the end.
"But I'll take it. It was definitely a big improvement on yesterday.
"To play the par fives on the front nine at even par was disappointing. I thought had I got to seven it would have been a good effort and that's sort of what my goal was over those last few holes.
I need to go out there tomorrow and shoot something probably a little better than I did today to give myself a real chance on Sunday
"Didn't quite happen but, as I said, it was a much better effort than it was yesterday."
"I feel like it's the momentum when it's going with you on a week like this, it's great," he said. "But whenever you're sort of struggling, it feels almost like more of an uphill battle.
"It was nice out there today. I made a few birdies and the crowd got behind me and it was nice to feel that."