World number eight Janko Tipsarevic completed a rare double-bagel win over late replacement Lovro Zovko to seal victory for Serbia over Croatia in the Blue Group of the World Team Cup in Dusseldorf.
Following Viktor Troicki's win over Ivan Dodig on Sunday, Tipsarevic gave Serbia an unassailable 2-0 lead by beating Zovko - a late replacement for Ivo Karlovic - 6-0 6-0 in just 46 minutes, losing only eight points on serve.
Zovko later regrouped for the dead doubles rubber alongside team-mate Dodig, and the Croatian pair gained some consolation as they wrapped up a 7-6 (7-5) 7-6 (7-4) win over Troicki and Nenad Zimonjic.
Also in the Blue Group, hosts Germany completed a 3-0 whitewash of Russia. Florian Mayer beat Igor Andreev 6-2 7-6 (9-7), then Mayer teamed with Christopher Kas to beat Igor Kunitsyn and Dmitry Tursunov 6-4 3-6 10-8 in the doubles rubber.
Tomas Berdych led the Czech Republic's fightback to secure a 2-1 win over Japan after the Czechs had been shocked on Sunday by Tatsuma Ito's win in the opening rubber over Radek Stepanek.
Berdych beat Japan's world number 60 Go Soeda 6-1 4-6 6-1 in just over two hours, then Stepanek and Frantisek Cermak joined together to beat Ito and Soeda 6-2 7-6 (7-4) in the decisive doubles.