McIlroy is expected to have plenty of home support

McIlroy has looked a certainty for selection for over a year but Caldwell has forced himself on to the team with some superb form this year.

He gained four points out of a possible six when helping Ireland claim the European Team Championship this summer.

Teenager McIlroy won the amateur silver medal at the recent Open Championship.

Caldwell formed a winning partnership with McIlroy at the European Team Championships last month while the Clandeboye player also shot an amateur course record of 65 that week at Western Gailes.

Other Ulster players Gareth Shaw and East of Ireland winner Richard Kilpatrick had also held outside hopes of making the team but they have missed out along with Baltray's Simon Ward and Shane Lowry.

Eighteen-year-old McIlroy from Holywood was the only amateur to complete 72 holes at Carnoustie.

He won the European Amateur title last year and plans to turn professional immediately after the Walker Cup.

Rhys Davies, Nigel Edwards and Lloyd Saltman, who all played in the 2005 event, have also been chosen.

The competition takes place at Royal County Down from 8-9 September.

Great Britain were edged out 12�-11� by the US two years ago, but selectors are confident they can emerge victorious on home soil.

Tony Disley, chairman of the R&A selection committee said: "We have picked a strong team that is more than capable of defeating the Americans at Royal County Down.

"The team not only includes players with experience at the highest level but has a number of exciting younger players who we believe will excel on the occasion."