The Scot looked to be questioning the wisdom of switching surfaces so quickly to the one which caused his back the most trouble before he underwent surgery in September. But although he woke up stiff and sore yesterday, Murray has renewed his commitment to the Davis Cup and will lead Britain as they return to the elite World Group for the first time since 2008.
The word from the Murray camp yesterday was that the Scot is looking forward to the challenge of taking on the United States in their back yard, even if he may have to play all three matches to give his side a chance of victory.
Murray had suggested that he might go home before making the trip to the west coast of America, but a quick look at an atlas would have made him realise that was probably not the best idea, in terms of overcoming jet lag.
With the tie beginning a week on Friday, Murray will spend a couple of days getting over the disappointment of losing to Federer and getting ready mentally for the Davis Cup match, before flying to San Diego on Sunday.
Reaching the quarter-final after just two competitive matches in four months was a an admirable achievement from Murray, even if he will fall at least two places in the rankings to No. 6. That will take him below Juan Martin Del Potro and Stan Wawrinka, who last night reached his first grand slam final.
Should Federer beat world No. 1 Rafael Nadal in the second semi-final, to be played this morning UK time, Murray would slip to No. 7, his lowest ranking since July 2008.
Murray has been away from home for several months now and he seems likely to go home to the UK after the Davis Cup. His next assignment would then not be until the week beginning February 24, on hard courts in Acapulco.
The good news is that Murray is not feeling any significant pain in his back and can hope to ascend the rankings again quickly. "I'm happy with the way it's held up," he said.