Andy makes Davis Cup promise to underdogs

Britain, without their No1 who has a knee injury, are huge underdogs for the tie in Buenos Aires, where Argentina are as short as 1-250 to win, and defeat will mean they will face a play-off in September to keep their place in the World Group.

Murray insists he will be available for that tie and for other Davis Cup commitments.

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Lloyd said: "I've spoken to Andy and we had a good chat. He said it's a one-off and he's available for our next match, which is great news. I told him on the phone I was sorry for him because this will be a great occasion whatever happens. I felt he had the ability to win both matches."

Andy was criticised by his brother Jamie for pulling out but Lloyd does not think there is a problem between the Murrays.

He added: "You have a few little disagreements but the bottom line is you're brothers. I don't think there'll be any problems in the future, we're all a bit frustrated about this match but we're moving on now.

"They have a great relationship, you only have to look at the way Andy reacts when Jamie's playing - he's more nervous than anyone. That's what being brothers is about. You're going to have a few little niggles but the bottom line is we're all going to be fine."

Jamie Baker insists he has what it takes to cause a huge upset and get Great Britain's Davis Cup tie off to a winning start. The world No 235 will have to play the match of his life if he is to beat the ninth-ranked David Nalbandian in the opening rubber.

Baker, whose two previous Davis Cup appearance were dead-rubber defeats, said: "I am excited. It is my first live rubber playing for my country. I will be concentrating on playing as well as I can."

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The three Argentina players scheduled to take part are all inside the world's top 100, with Alex Bogdanovic the highest-ranked Briton below Murray at 188.

Even with world No12 Murray in tow, the visitors would have been facing a tall order, with Argentina playing on their favoured clay.

However, today's second rubber does present an outside hope of an upset, with Serbia-born Bogdanovic taking on Agustin Calleri.

The world No 41 has not played a singles rubber since April 2006 and will be under pressure to produce the goods. Tomorrow's doubles rubber sees Jamie Murray join forces with debutant Ross Hutchins against Nalbandian and Jose Acasuso.

Murray senior knows Britain must win that rubber if they are to stand any chance of clinching the tie.

He said: "The doubles match is going to be our best chance to try to win some rubbers."