"We are right where we want to be going into tomorrow," McDowell told reporters.

"The leaderboard was really going to not mean anything until tonight and we are two shots ahead going into tomorrow, but there are some great teams up there, some great players.

"We are going to have to go and play well tomorrow but this is where we want to be. We are both playing lovely. I managed to heat my putter up today and make a few, and we are very excited looking forward to tomorrow."

Ireland wasted no time improving their overnight score with five birdies in their opening seven holes to reach the turn in 31.

McIlroy and McDowell then picked up three more coming home to put themselves in a good position to go one better than 2009, when they finished runners-up to Italy.

"We thought something similar to the first day was going to be a solid score and we ended up sort of coming one short of that," said McIlroy.

"But anything around eight, nine, 10-under par is a good score in that format, and I was just lucky enough that Graeme played very, very well today and holed a lot of great putts. I was a spectator for the majority of the round, but it was good."

Germany and South Africa thrust themselves into contention on 19 under par with rounds of 61.

Germany, represented by Martin Kaymer and Alex Cejka, tore up the Blackstone course with 11 birdies, a feat matched by South Africans Louis Oosthuizen and Charl Schwartzel.

"That was our goal, to close the gap a little bit," said Cejka.

"We knew we had to go low in that format today. We kind of got lucky that we made birdies on different holes. I think we played pretty solid and we are looking forward to tomorrow's format."

Schwartzel felt an improvement on the greens paid dividends for South Africa.

"We scored very well today. The first two days, we really struggled with putting and today the first few holes we didn't make any putts," he said.

"But then from seven, eight, nine, we made three birdies in a row, so suddenly we felt like we were back to our normal selves. Yesterday our score was the worst we could have had, we were playing well but we couldn't putt. Now we have a good chance going into tomorrow, and it's always an honour to play for your country."

The duo were joined on 19-under-par by the United States as Matt Kuchar and Gary Woodland posted a 63 containing 10 birdies and a bogey while Australia slipped to fifth as a 67 left them 18 under.

Scotland lie six shots off the pace on 15-under after Martin Laird and Stephen Gallacher could only manage a 69, joining Wales after Rhys Davies and Jamie Donaldson returned a 65.

English duo Ian Poulter and Justin Rose, meanwhile, were languishing in 15th on 13-under-par following a 68.