Jack Sock and John Isner won their singles matches on Friday to give the United States a 2-0 lead over Switzerland in first-round Davis Cup competition in Birmingham, Ala.
Sock, the top-ranked American and the No. 20th player in the world, easily defeated 146th-ranked Marco Chiudinelli 6-4, 6-3, 6-1 in the opening match on the indoor hardcourts at Legacy Arena.
Chiudinelli fought off five set points in the first set before Sock won it on his sixth set-point opportunity. Sock rolled from there.
Isner, the second-ranked American and the No. 23rd player in the world, had a more difficult time with Henri Laaksonen. Isner dropped the first set, but then breezed to a 4-6, 6-2, 6-2, 7-6 (1) victory that took two hours and 44 minutes.
The United States has now won 11 consecutive rubbers (Davis Cup matches) against the Swiss. In 2012 the Americans won 5-0 against the Swiss, and in 2009 they won the last four matches.
"There were a few extra nerves I think playing Davis Cup," Sock said. "When you're playing for your country, being part of a team, maybe at a normal event, normal tournament, you come out swinging a little bit more.
"I think I was a little hesitant at the beginning, maybe too conservative playing when obviously my game is to kind of play big and hit forehands and be aggressive.
"But after getting the break (to win the first set) it loosened me up a little bit and I was able to play a little bit bigger. That's how I like to see matches go. I love playing in front of a home crowd. I love playing at home, especially Davis Cup. I love being on the team."
The U.S. is a heavy favorite to eliminate the Swiss team, as Roger Federer and Stan Wawrinka are not playing for Switzerland in this first-round competition.
If the Americans eliminate Switzerland, their quarterfinal opponent would be Australia, which became the first country to advance to the next round.
Australia's John Peers and Sam Groth posted a 6-3, 6-2, 6-2 doubles win over Jiri Vesely and Jan Satral on Saturday in Melbourne, Australia, to give Australia a 3-0 lead, clinching the first-round victory over the Czech Republic.
On Friday, Jordan Thompson got Australia off to a good start by beating Vesely 6-3, 6-3, 6-4, and Nick Kyrgios made it 2-0 with his 6-2, 6-3, 6-2 triumph over Satral.
Serbia, France and Italy took 2-0 leads in their first-round matches.
Serbia's Novak Djokovic lost the first set to Russia's Daniil Medvedev, but Djokovic ended up winning 3-6, 6-4, 6-1, 1-0 when Medvedev retired due to injury. That came after Viktor Troicki outlasted Russia's Karen Khachanov 6-4, 6-7 (3), 6-3, 1-6, 7-6 (6) in Nis, Serbia.
Paolo Lorenzi of Italy won the opening singles match against Argentina in Buenos Aires by beating Guida Pella 6-3, 6-3, 6-3. Andreas Seppi made it 2-0 with a 6-1, 6-2, 1-6, 7-6 (6) victory over Carlos Berlocq.
Spain and Croatia stood at 1-1 in Osijek, Croatia, after Franko Skugor of Croatia defeated Pablo Carreno Busta 3-6, 6-3, 6-4, 6-4, 7-6 (6), and Roberto Bautista Agut of Spain beat Ante Pavic 6-4, 6-2, 6-3.
Belgium and Germany are tied 1-1 in Frankfort, Germany, after Belgium's Steve Darcis defeated Philipp Kohlschreiber 6-4, 2-6, 3-6, 7-6 (2), 7-6 (5), and Germany's Arthur De Greef knocked off Alexander Zverev 6-3, 6-3, 6-4.
Great Britain and Canada also are tied at 1-1 in Ottawa, Canada, after Canada's Vasek Pospisil defeated Kyle Edmund 6-4, 6-1, 7-6 (3), and Daniel Evans of Great Britain defeated Denis Shapovalov 6-3, 6-3, 6-4.