Huge shock or cheeky bluff? Juan Martin Del Potro 'a serious doubt' for final rubber against Britain

Del Potro told Argentine media after the doubles defeat to the Murray brothers on Saturday evening that he "wants to play... many years, not one more match".

The quote sounded like a serious suggestion that he would not risk playing after having endured so much injury pain over the last few years.

"My legs hurt, wrist, back, right shoulder... but I'm still standing," Del Potro was quoted as saying in La Nacion.

"My goal is to finish the year healthy. I fought hard to return to tennis the last two years... I have to be smart because it is the beginning of a new kind of career.

"I made a great effort during the week and hope to finish healthy."

Journalists were split on whether or not Del Potro will end up playing the final rubber - probably against Dan Evans, who is expected to see off competition from Kyle Edmund, who lost to Guido Pella in four sets on Friday, for the final match.

Eurosport analyst Greg Rusedski put the potential impact of Del Potro not appearing for the fifth rubber in context when he explained what a huge boost it would represent for Britain.

Rusedski made it clear that if Del Potro were to not appear for the final rubber, "it would be the biggest Davis Cup surprise of all-time".

It would be absolutely huge for Britain if Del Potro were to be unavailable for the final rubber - and a problem entirely of Argentina coach Daniel Orsanic's own making.

Everyone was shocked to see the former world number four turn out for the doubles match on Saturday, and it appeared to be a needless gamble from Orsanic in trying to wrap up the tie a day early.

It clearly backfired as the Murray brothers won the doubles rubber and took the tie to the final day - and now Del Potro is placed in the awkward position of having to choose between his own health and fitness and the desire to take his country to the Davis Cup final in an event they have never won.

Given the way Del Potro has battled back from persistent, and pretty horrific injuries over the last few years, it would be completely understandable if he were to step out of the final rubber. But you would still expect him to play if - as is very much expected - the tie goes to a decider.