PARIS (AFP) - Britain have no room for error on Sunday in their Davis Cup semi-final against Argentina, needing to win both reverse singles rubbers to secure a place in the men's team tennis tournament's final.
The other semi-final between Croatia and France also hangs in the balance, with 2005 winners Croatia heading into the final day in Zadar 2-1 up.
In Glasgow, Andy Murray and brother Jamie clinched the doubles rubber on Saturday to keep the reigning champions' hopes alive, after they went 0-2 down on a disastrous first day.
World No. 2 Andy was back in action first on Sunday in the reverse singles against Guido Pella, ranked 49 in the world.
Murray started strongly, taking the first set 6-3, and the second 6-2. Victory for Murray would ensure that the match would hinge on a decisive final rubber between Britain's Kyle Edmund and probably Juan Martin del Potro.
Leading 2-0 from Friday's singles, Argentina captain Daniel Orsanic selected del Potro alongside Leonardo Mayer instead of Federico Delbonis as he looked to kill off the semi-final.
However, the tactic backfired as Murray and his older brother Jamie secured a thrilling victory.
Argentina are looking to reach their fourth final in 10 years in Glasgow while in Zadar, Croatia, Marin Cilic was facing France's Richard Gasquet in the first of the two reverse singles on Sunday.
Cilic and Ivan Dodig downed top-ranked French pair Pierre-Hugues Herbert and Nicolas Mahut 7-6 (8-6), 5-7, 7-6 (8-6), 6-3 in Saturday's doubles.
In Glasgow, Edmund is scheduled to face del Potro in the second match, although the Argentinian star hinted that he may sit out what could be the decisive rubber.
In his absence, Argentina could call on either Delbonis or Mayer.
Cilic was a surprise call-up for the doubles for Croatia as he replaced Marin Draganja.
But he didn't let his side down as he secured his second point of the weekend when he and Ivan Dodig downed Herbert and Mahut to follow their win over Bob and Mike Bryan in the quarter-final success against the United States.
After Cilic faces Gasquet, the second reverse singles will see Borna Coric tackle Lucas Pouille.
On Friday, Gasquet beat Coric 6-2, 7-6 (7-5), 6-1 before Cilic saw off Pouille 6-1, 7-6 (7-4), 2-6, 6-2.
In the play-offs, where the winners earn places in the World Group in 2017, Olympic champions Rafael Nadal and Marc Lopez beat Leander Paes and Saketh Myneni 4-6, 7-6 (7-2), 6-4, 6-4 to secure a 3-0 triumph for Spain over India in New Delhi.
In Sydney, John Peers and Sam Groth earned a 6-4, 6-2, 6-7 (3-7), 7-6 (7-2) win and an unassailable 3-0 advantage for Australia against Slovakia. Rain washed out the final day on Sunday.
Belgium, last year's runners-up, also secured their World Group status thanks to a 3-0 victory over Brazil in Belgium. Japan made sure of their place in the elite section with a 3-0 victory over Ukraine in Osaka.
In other ties, Canada beat Chile 3-0, Switzerland and Uzbekistan were 2-2, Russia were 2-1 to the good over Kazakhstan in a rain-hit tie while Germany were level 2-2 with Poland.