Erste Bank Open: Britain's Dan Evans retires injured against Frances Tiafoe in Vienna

 The British number two was leading 4-1 in the first round when he pulled up sharply at the baseline.

Evans, 33, looked forlorn as he received treatment and it soon became clear he would be unable to continue.

On Monday, Evans was named in Britain's team for next month's Davis Cup Finals.

Evans was instrumental in helping his nation qualify for the knockout stage of the men's team event and will be hoping the injury is not serious enough to rule him out.

Britain take on Serbia in the last eight on 23 November, with the semi-finals and final taking place later that week in Malaga.

Evans was in total command against American world number 14 Tiafoe in Vienna when he appeared to pop his right calf muscle attempting to sprint forward from the baseline.

The world number 35 had dominated on serve and troubled the out-of-sorts Tiafoe with his clean returning, taking one of four break points before looking to further close in on the opening set.

But early in the sixth game, Evans let out an anguished cry as he spun around in pain and shock.

Immediately hopping towards his chair, Evans signalled for treatment and the gravity of the injury left him visibly frustrated.

The Briton appeared to tell the physio he could not walk and within moments it was obvious he would not be able to continue.

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Four weeks before the Davis Cup Finals, Dan Evans staggered off the court after retiring from his Erste Bank Open match against Frances Tiafoe due to what appeared to be a significant calf injury.

In the opening round, the British number two was ahead 4-1 when he suddenly pulled up at the baseline.

Evans, 33, was despondent while he underwent treatment, and it quickly became apparent that he wouldn't be able to go on.

Evans was selected on Monday to play for Great Britain in the Davis Cup Finals later this month.

Evans will be hopeful that the injury is not severe enough to keep him out because he was crucial in enabling his country get to the knockout round of the men's team competition.

On November 23, Serbia will play host to the last eight, with the semifinals and championship game taking place in Malaga the following week

When he looked to pop his right calf muscle while trying to surge forward from the baseline against American world number 14 Tiafoe in Vienna, Evans was in complete control of the match.

The 35th-ranked player in the world had an advantage on serve and plagued the unfocused Tiafoe with his accurate returning. He converted one of four break opportunities before trying to take the first set even more tightly.

Evans, however, cried out in agony early in the sixth game as he turned around in discomfort and disbelief.

Evans immediately sprung to his chair and motioned for help, clearly irritated by the seriousness of the wound.

The British man appeared to inform the physiotherapist that he was unable to walk, and it became clear very quickly that he would be unable to go on.

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