(Reuters) -Davis Cup heavyweights Australia and the United States eased through the first qualifying round on Saturday but Britain were knocked out as Japan hit back from 2-1 down to win 3-2, while Denmark staged a dramatic comeback to overcome Serbia.

Japan fought back from 2-1 down to beat Britain 3-2 in their Davis Cup qualifier on Saturday to advance to the second round while the United States sealed a 4-0 victory over Taiwan.

Great Britain’s ambitions of reaching the second round of the Davis Cup qualifiers were dashed by a 3-2 defeat to Japan.

Alex Michelsen gave the United States a 2-0 lead over Taiwan on his Davis Cup debut in the first round qualifiers on Friday, while Jacob Fearnley also impressed in his first appearance in the competition to pull Britain level with Japan.

Jacob Fearnley and Billy Harris both lost their singles matches on Saturday as Japan earned a 3-2 Davis Cup win over Great Britain in Miki, Japan to send Leon Smith's team to a relegation playoff.

Davis Cup heavyweights Australia and the United States eased through the first qualifying round on Saturday but Britain were knocked out as Japan hit back from 2-1 down to win 3-2.Australia, whose 28 Davis Cup titles is only bettered by the 32 of the U.

Japan came from behind to beat Britain 3-2 in Davis Cup qualifying on Saturday, while Serbia face a relegation play-off after squandering a 2-0 lead in their loss to Denmark. It's the first time in Danish Davis Cup history that we managed to come back from 0-2 down and I'm beyond delighted,