Argentina on brink of early exit, Australia through

Croatia, runners-up last year, were without their top man Marin Cilic but managed to end the opening singles level 1-1 with a Spanish team lacking Rafa Nadal after Franko Skugor upset Pablo Carreno Busta over five sets. 

Only Serbia, champions in 2010 and facing Russia at home in Nis, had the services of a top 10 player in Novak Djokovic and they took a 2-0 lead. Djokovic, who readjusted his start to the season after a shock early exit from the Australian Open, had a scare when he dropped the first set to Daniil Medvedev but prevailed 3-6 6-4 6-1 1-0 when the young Russian retired. 

Viktor Troicki had earlier beaten Karen Khachanov 6-4 6-7(3) 6-3 1-6 7-6(6). 

Del Potro, like most of tennis’s leading men, had announced before the season began he would not be available for the opening round of the World Group. 

This left top seeds Argentina, a British team without Andy Murray and the Swiss minus Roger Federer and Stan Wawrinka vulnerable to defeat. Argentina won away in every round last year, but in Buenos Aires Guido Pella lost 6-3 6-3 6-3 to Paolo Lorenzi and Andreas Seppi beat Carlos Berlocq 6-1 6-2 1-6 7-6(6) to leave the holders on the brink of elimination. 

Croatian Skugor, ranked nearly 200 places below Carreno Busta, won 3-6 6-3 6-4 4-6 7-6(6) in just over four hours in Osijek before Spain recovered with Roberto Bautista Agut’s 6-4 6-2 6-3 win over Ante Pavic. 

Earlier, Steve Darcis had come back from 3-0 down in the fifth set to beat Phillip Kohlschreiber 6-4 3-6 2-6 7-6(2) 7-6(5). Britain, facing a Canada team without Milos Raonic in Ottawa, made a good start when Dan Evans beat Denis Shapalov 6-3 6-3 6-4 but Vasek Pospisil hit back to level the tie with a 6-4 6-1 7-6(3) win over Kyle Edmund.