When Great Britain got the better of a weakened Croatian side in their World Group playoff in September, all eyes quickly focussed on who would lie in wait for Leon Smith's rejuvenated side for their first appearance in the top tier of the competition in several years.
A trip to face Rafael Nadal on the Spanish clay courts was feared, as was a journey to Belgrade to meet Novak Djokovic's Serbia, but when the draw was made, it pitted Great Britain with a trip to North America to face USA.
It could have been worse for a team headed by Andy Murray, but as Sports Mole suggests, Great Britain have a huge fight on their hands if they want to progress in the competition.
Isner's absence has resulted in Donald Young being drafted into the lineup, but while the American number three is ranked sufficiently higher than Great Britian's second player James Ward, he has never won a match at the French Open.
Teammate Sam Querrey has reached the third round at Roland Garros on three occasions, and while he would most likely get out-thought by Murray, he will be expected to get a win on the board against Ward
Much of the Bryan brothers' success has come away from the clay, but they have still won the title at Roland Garros on two occasions, while they still head the ATP doubles rankings by nearly 6,000 points.
They will be favourites to beat Colin Fleming and one of Murray or Dominic Inglot, but it's not a foregone conclusion that they will record a win in what could prove to be a decisive match in the tie.
Despite knowing his team's opponents for several months, Leon Smith has been unable to finalise his plans for the tie until he was assured of Andy Murray's fitness.
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Murray may have lost to Roger Federer in the quarter-finals of the Australian Open, but the Wimbledon champion came through with flying colours, and it's imperative that the Scot chips in with two wins if Great Britain are to stand the best possible chance of winning in San Diego.
Ward is ranked inside the world's top 200 but despite growing up on the clay courts in Spain, he has registered just one win during the first month of the year.
Smith will also be relying on his doubles team to surprise the home crowd by defeating Bob and Mike Bryan to try to ensure that USA don't open up an advantage going into the third and final day.
As with many of Great Britain's Davis Cup ties, much will depend on Andy Murray. If the Scot can register two wins in the singles, then the visitors will have a great chance of causing a surprise in San Diego.
However, if there are any issues with Murray's transition from hard to clay, then Great Britain will be up against it against the more experienced Americans.
If all goes well with Murray, then expect Saturday's doubles encounter with the Bryan brothers to decide the victors of the tie, but the 15-time Grand Slam winners might have too much court-craft for the Brits. 3-2 to USA.