Ireland opened their World Cup campaign with a workmanlike victory over the United States in New Plymouth.

Both teams had to contend with atrocious conditions in a match which pitched the Irish against their former coach Eddie O'Sullivan, now boss of the Eagles.

Ireland piled on the pressure near the end but failed to get a bonus-point try while the USA managed to cross in injury time, outside centre Paul Emerick touching down for an interception score.

The United States should be proud of their defensive effort, one that saw them fare better than the last time the two teams met - a 45-point hammering in Ireland's favour at Landsdowne Road in 1999.

Both teams wore black armbands and observed a moment's silence to mark the 10th anniversary of the 9/11 terrorist attacks in New York.

Ireland were the team looking to attack early on, but their handling errors and a spirited showing in defence from the United States meant the favourites had to settle for just a Jonathan Sexton penalty from the opening exchanges.

At times Ireland looked effective but their lack of control under the high ball and the absence of a finishing touch meant their opportunities were limited.

Just as it looked like they would only be ahead by three points at halftime, Tommy Bowe ensured there was a degree of comfort in the scoreline for Ireland when he touched down near the posts to the relief of the Irish fans.

Sexton converted his own try before heading to the halftime break with Ireland ahead 10-0.

The USA were first to register points in the second half through James Paterson's penalty, but it was all Ireland from then on.

And with fewer errors in the second half, the heavyweights looked dangerous.

Lock Donncha O'Callaghan provided the impetus for Ireland's second try by securing the lineout, before some solid attacking work from the forwards paved the way for hooker Rory Best to touch down.

Substitute Ronan O'Gara missed the conversion, but was given another opportunity soon after thanks to Ireland scoring their second try in the space of five minutes.

Bowe received a clever inside pass from stalwart Brian O'Driscoll to score Ireland's third try of the match, and this time O'Gara converted.

The United States continued to valiantly defend their line, and claimed a consolation try in the final act of the game through an intercept to centre Paul Emerick.

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