USA midfielder Michael Bradley believes Ghana are a major threat to them at Brazil 2014 after the Black Stars brushed aside Korea Republic 4-0 in a pre-World Cup friendly on Tuesday.

He said the Stars and Stripes are fully aware of the troubles the four-time African champions could cause in the opening game in Group G.

“It would be easy to look at the end and say '4-0 what a performance,'” Bradley said at the team's training base. “But still, it's a warm-up game.”

“Regardless of how the game went, we have a lot of respect for Ghana. They're a good team. We know that they're dangerous. They can cause trouble.”

The Americans are doing everything right for a better start to the World Cup against Ghana but Bradley has admitted talk is cheaper than action.

“The first game is so important. So we certainly made no secret that all the focus at this point is about Ghana and making sure we do everything we can spot.

“We can sit here now and talk about wanting to start well. But just because you talk about it doesn't mean it is guaranteed,” he noted.

The 26-year-old midfielder insists Ghana have a different team compared to the one they played in Rustenburg, South Africa last four years, noting that Kwesi Appiah’s side have technically-gifted players who can punish teams with half chances.

“I do think that it's a different team than the one we played in 2010,” Bradley said of Ghana. “I remember quite a bit about the game, for a majority of it we were the ones in control and pushing things and looking to get back to 1-1, and once we did get back to 1-1 we were still pushing for a winner.

“Ghana have guys who have a mix of athleticism and technical ability; the way that they can take certain plays and improvise and turn a half play into a chance all of a sudden. We have to understand what they're all about."

Bradley has played 86 times for the US scoring 12 goals. Ghana have beaten USA 2-1 twice in the group stages and round of 16 of the World Cup in 2006 and 2010 respectively.