ANDY MURRAY could be forgiven for being a tad unhappy with his lot right now.

Unceremoniously dumped out of the Australian Open by Roger Federer and with his rehabilitation from back surgery still not complete, the start of 2014 hasn't exactly been straightforward.

Leaving Melbourne's hard courts for California for a far-from-perfect clay court housed in a baseball stadium - albeit a beautiful, striking one in in the heart of vibrant San Diego - is not what the doctor would order as the Wimbledon champion seeks a return to full fitness.

Yet, it was hard to keep that mischievous grin off Murray's face in the build up to Great Britain's first match on their return to the World Group which starts today against the United States.

Indeed, a smile turned to something of a scowl when the Scot was quizzed about Twitter wind-ups and false marriage proposals.

Murray, always one for a joke no matter what the interpretation of his public persona might be, knew exactly what he was doing and what reaction it would provoke - even if he expressed his incredulity that there might actually be people who believe everything he says.

If anything, it just showed that when he, or most players for that matter, swap the grind and solitude of the tour for a week sucked into a team environment, a real spirit of fun and sense of camaraderie permeates the group.

Leon Smith, the captain who has been showing unusual flashes of paranoia in the build up by limiting the British press to watching no more than five minutes of practice, has been keen to ensure his troops are enjoying the experience.

Team members have been forced into singing on a nightly basis while card games have been organised to keep the competitive streak going off the court. It's not exactly a boot camp for Murray, James Ward, Colin Fleming and Dom Inglot but when the action begins, those smiles will be replaced by game faces.

A positive start in the singles, where Murray plays Donald Young, and Ward takes on world No.49 Sam Querrey is key because the Bryan Brothers, the world No.1s, lie in wait in tomorrow's doubles. Inglot, who enjoyed a fine run in Melbourne by reaching the quarter-finals of the doubles, gives Smith the option of resting Murray for the final singles on Sunday but the Scot, sore back and all, remains on course to play in all three rubbers.

As such, the singles will determine if Smith's men have any chance of building on the successes of last year by moving on to the next stage. The US though, led by Jim Courier, remain confident of standing firm in the face of whatever Murray and co throw at them.

But with the huge-serving John Isner missing out with the ankle problem that ruined his Australian Open campaign, the hosts are not without their problems. It is an undoubtedly big blow for the Americans.

"We knew John wasn't going to play earlier in the week and he's hardly hit a ball so we have given Donald the chance to practice and get ready," said Courier.

Murray though is unsure of how the freshly laid courts will play. Clay surfaces here in the US don't resemble the red dirt used at the likes of Roland Garros and throughout Europe.

"The venue looks incredible and it is not easy to put a temporary court down. But the gamble is it won't be perfect. It is hard for the clay to embed itself," said Smith. "Conditions are changing a bit, it's not as hot as it was so there is no advantage for them."

Kyle Edmund,who was put through his paces against Ward in practice, recently won two Futures events on the green clay of Florida , which is a far more lucid, quick surface than most are used to. Smith has opted for Ward's experience instead, however.

"It's very, very slippy and not really red clay to be honest,"said Murray. "I just hope the court put down is safe and okay for the players to perform. It will be tough for everyone. The court will certainly be testing for the big guys on their team to move. It's quick, a lot quicker than the surfaces we normally play on in Monte Carlo, Rome, Madrid or Roland Garros. The last few days have been very different. I'm hitting the ball fine, it's just getting used to the way we have got to move. All the players have been struggling.

"It's been a while since we last played against each other but this competition has a great history between the two countries. It should be a fun match. There is a different kind of pressure playing in the Davis Cup. Instead of leaving the courts after the matches you stay around and support the others. They can be long days but exciting ones, too.

"Being in the team environment, it's obviously the fun part of the competition, it's what makes it different, we get to hang out for four or five days before the tie most of the time. Everyone has a good time."