The United States, pictured, beat Argentina to reach the final of the Junior Davis Cup ©ITF

The Czech Republic and the United States earned hard-fought semi-final victories to secure their places in the 2017 Junior Davis Cup final.

Wins for Jonas Forejtek and Dalibor Szrcina saw the Czechs, the tournament's top seeds, defeat Croatia after the singles rubbers at the Hungarian National Tennis Centre in Budapest.

The Americans, however, were pushed all the way to the tie break of the decisive doubles rubber against Argentina.

Szrcina was forced to come from a set down to win for the Czechs, beating Croatia's Duje Ajdukovic 2-6, 7-5, 6-2.

Earlier in the day, Forejtek claimed a comfortable 7-5, 6-2 triumph against Admir Kalender.

In the other tie of the day, Argentinian Juan Cerundolo defeated William Grant of the US in the first rubber 7-6, 7-5 to put his team ahead.

But his teammate Thiago Tirante struggled in the second rubber, dropping the first set to Govind Nanda after only around half an hour.

He battled back in the second, but Nanda went on to claim a comfortable 6-1, 6-4 victory to level the tie.

Into the doubles the match went and Tirante responded well to the disappointment of losing his singles rubber as he took the first set alongside partner Alejo Lingua.

But Nanda and Tyler Zink clawed their way back into the match to take the second set, before going on to claim a 4-6, 6-2, 10-5 victory.

Japan, pictured, will play the US in the women's Fed Cup final ©ITF
Japan, pictured, will play the US in the women's Fed Cup final ©ITF

The US also booked their place in the final of the women's Junior Fed Cup competition.

The Americans and Japan both battled through deciding doubles rubbers to win their respective semi-finals.

Canada started the stronger against the US in blustery conditions with Leylah Annie Fernandez recording a 6-4, 7-5 victory over Caty McNally.

But French Open girls' singles champion Whitney Osuigwe levelled the tie with a 6-4, 6-2 triumph against Layne Sleeth.

The Americans then combined to record a 6-3, 7-5 victory over Fernandez and Sleeth in the doubles.

Japan reached the first Junior Fed Cup final in their history after a battling performance against Ukraine in the other semi-final, with Yuki Naito and Naho Sato emerging victorious in tense deciding doubles rubber.

In the singles, Sato fought back from a set down against Daria Snigur to win 3-6, 6-4, 6-1, but Marta Kostyuk defeated Naito 6-3, 6-4 to level the tie.

Japan would ultimately prevail though, winning the doubles match 7-5, 6-7, 10-3 against Kostyuk and Alina Tsyurpalevych.