Matteo Manassero has handled the brunt of the afternoon cold and wind, making two eagles on his way to a five-under 66 and a one-shot lead at halfway in the Irish Open.

Home favourite Rory McIlroy caught a break with the weather in the morning but failed to capitalise as much as he would have liked during Friday's second round.

McIlroy started on the back nine at Royal County Down in moderate conditions, failed to birdie the par fives and had a 70 to finish two shots behind.

Temperatures dropped severely in the afternoon and players were wearing hand warmers to cope with the cold.

Manassero opened with an eight-foot eagle putt, and the Italian recorded another eagle with an iron to 2 feet on the par-5 12th.

It was a struggle coming in with the wind, and he twice escaped trouble to make par.

Manassero, who won this year in South Africa on the European tour, was at six under on 136.

He was one shot ahead of Todd Clements (71) and Laurie Canter (68), with McIlroy tied with Ewen Ferguson of Scotland (69) and Alejandro Del Rey of Spain (71).

Another shot behind was Daniel Brown, who was tied for the lead until getting caught in the thick grass and native areas at Royal County Down, taking a triple bogey on his final hole at the par-four ninth and wiping out a good day's work. He wound up with a one-under 70.

McIlroy, who grew up about 60km to the north in Holywood, was satisfied with his position going into the weekend, yet still disappointed he didn't do more.

"I felt like the course was there a little bit for the taking this morning," he said. "We started on the back nine, too. I was a little disappointed."

He hit into a pot bunker on the 12th and missed the fairway on the 18th, both times having to lay up on the par fives. But he made the turn and hit 8-iron to 15 feet for eagle.

"I played pretty solid on the way in," he said. "Felt like I left a couple of shots out there but, you know, still in a good position."

It was better than his last Irish Open at Royal County Down in 2015, when he opened with an 80 and missed the cut.

"Much better than nine years ago when I was watching the third round on TV," McIlroy said. "Happy to be here for the weekend and happy to give myself a chance."

Australian Jason Scrivener made the cut with a two-under 69 leaving him at one over for the tournament in joint-47th place but David Micheluzzi's 72 wasn't enough to prevent his early exit at nine over.