Britain's Davis Cup hopes receive huge boost with Del Potro out of semi-final decider

World number 53 Dan Evans will instead face 114th-ranked Leonardo Mayer with the winner of that match securing a place in the final of the Davis Cup against Croatia - who beat France in the other semi-final on Sunday - after world number two Andy Murray levelled the semi-final in Glasgow at 2-2 with a 6-3 6-2 6-3 singles win over Guido Pella despite battling a thigh injury and tiredness.

If Evans, preferred to Kyle Edmund after he lost in four sets to Pella on Friday evening, can produce victory against Mayer over five sets, Britain will return to the Emirates Arena in Glasgow on November 25-27 with the chance of winning back-to-back Davis Cups following their success in Belgium last November.

Del Potro had told media in Argentina after he and Mayer suffered doubles defeat to Andy and Jamie Murray on Saturday evening that he "wants to play..many years, not one more match".

It sounded like Del Potro would not risk playing having endured so many wrist problems over the past few years, and it turned out not to be a bluff after he spent over eight hours on court on Friday and Saturday, including an epic five-set 6-4 5-7 6-7 6-3 6-4 win over Andy Murray on Friday.

It was a repeat of their Olympic singles final in Rio which Murray won and the longest match of their respecitve careers at over five hours.

It is the first time Evans, 26, and Mayer, 29, have met in their careers, but Evans will be boosted by his recent form in which he pushed Stanislas Wawrinka to match point in the US Open last 32, but the Swiss survived a huge scare to progress in five sets against the Brit before winning his third Grand Slam at Flushing Meadows.

If Argentina fail to reach the final, the decision to risk Del Potro in the doubles on Saturday will go down as one of the poorest in recent memory when a rested Del Potro would have started a huge favourite to complete victory for the four-times finalists in the deciding rubber in Scotland.