Davis handed Athens place Full GB track and field squad

Davis was called up for the 400m and 4x400m relay despite gaining a British passport less than two weeks ago.

He told BBC Five Live: "I was told there were a lot of athletes who were upset with my decision.

"But, like anywhere in the world, there is a certain standard that you have to hit. I did that and it has allowed me to go to the Olympics."

Davis qualified for the individual 400m after meeting the "A" standard by 0.03 seconds in Tucson, despite coming fifth at the British trials.

Thomas angry at selectors

He also claimed a relay place at the expense of veterans Iwan Thomas and Du'aine Ladejo.

The 26-year-old from Sacramento qualified for Britain because his mother was born in London, but his arrival for the trials in Manchester was his first visit to his adopted country.

Davis made an embarrassing slip-up on national radio by talking about "representing England".

But he added: "I've got my heart set on winning a medal. If I win a medal it's for all of Britain, definitely.

"I'm extremely happy, I'm excited. It was definitely up in the air because I know there were quite a few athletes that still were part of the selection process."

From a selector's point of view the guy has got a valid British passport Britain's athletics team leader Max Jones

Asked whether he felt what he had done was fair, Davis said: "I qualified for both [US and Great Britain] trials.

"I was just looking at opportunities to possibly run for another country and to reach my ultimate goal, which is the Olympics."

Britain's athletics team leader Max Jones defended the decision to select Davis.

"I can understand anyone thinking 'this guy has not been part of the system and has come late in the day', but perhaps that's life," said Jones.

"From a selector's point of view the guy has got a valid British passport.

"He did it all himself, got himself in line and he was there for selection."

Jones admitted Davis would not have stood a chance of making the American team for Athens.

But he said: "He's a very promising athlete, on the fringes of world class, and could help our relay team win in Athens.

"He was entitled to be selected and if we didn't select him on grounds of discrimination we could be in trouble."

Davis could now become eligible for lottery grants if he is accepted on to Britain's world-class performance plan.

"That decision will be taken at the end of the season, depending on how well he performs at the Olympics," said Jones.

"He will receive some help, with flights to Cyprus and into Athens, but he won't be formally on the world-class performance plan until post-Athens, if he qualifies."