The USA opened their CONCACAF Gold Cup account with a comprehensive 4-0 win over minnows Grenada while Honduras edged Haiti 1-0 in their first game.

Freddy Adu's second-ever international goal helped the defending regional champions USA to their dominant win over the islanders in Group B action. Stuart Holden, Robbie Rogers and Charlie Davies also scored for the Americans, who go top of the standings on goal difference.

Adu opened the scoring after the seventh minute when he collected a pass from Rogers, who was in fine form throughout, and fired home from 12 yards. Holden then increased the new-look USA's lead in the 31st minute when he headed home from close range.

Rogers scored his first-ever international goal on the hour mark when he latched onto a sharp through ball from Logan Pause before pushing his shot beyond goalkeeper Desmond Noel.

The USA continued to dominate possession and Davies, part of the American team that recently finished second at the FIFA Confederations Cup in South Africa, wrapped up the victory eight minutes later when he picked up a cross from Heath Pierce and flicked the ball home at the far post.

In the other game in the group, Carlos Costly's second-half header was enough to secure a 1-0 win for favourites Honduras over Haiti. The Poland-based striker headed home from a free-kick in the 76th minute after the Haitians had dominated possession for the majority of the game.

The Hondurans will now play the USA on Wednesday while Haiti look to get off the mark against Grenada.