Jamie Murray has described his disappointment at brother Andy's decision not to join his Great Britain team-mates in their Davis Cup clash against Argentina.

The World Group meeting, which starts on Thursday at Parque Roca, is a tough encounter for John Lloyd's recently-promoted team and Murray's withdrawal with a knee complaint has stacked the odds even further against them.

But the British number one's elder brother feels his decision to sit out the tie is overly cautious and would be happier to see him taking on the hosts despite his injury concerns.

"It kind of affects the way we feel about him. I think it's disappointing that he chose not to come. From what I have been reading he hasn't come out and said he's injured, it's more a prevention thing. I think if he had really wanted to push himself he could have come here," Murray senior told the Daily Mail.

Andy Murray is preparing to compete in an ATP event in Marseille instead of linking up with Lloyd and co. and it is not a decision which his brother can sympathise with.

"He obviously felt it was more important for him to concentrate on going to Marseilles and doing well rather than coming here.

"It was a shock to me and for the team it's very disappointing. I wasn't aware he had a problem. I last spoke to him in Australia just before he left (the Australian Open)."

"There's not much to say. I'm here working hard for the team and trying to do my best and he is at home doing whatever he is doing."

But if the elder Murray's words appear to betray a sense of bitterness, it is only because of the potential impact the world number 11 could have made on Great Britain's return to the top table of world tennis.

"He had the ability to win two singles matches here. He is in the top ten in the world and it's not by fluke," added Jamie.

Argentina have lost Juan Monaco to an ankle injury but can boast the talented Sebastian Prieto as his replacement in a team that also includes top-60 stars David Nalbandian (ninth), Agustin Calleri (41st) and Jose Acasuso (50th).

In the absence of 20-year-old Murray, Alex Bogdanovic is Lloyd's highest-ranked competitor with a placing of 188.